diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..95c4320
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,5 @@
+.DS_Store
+/.build
+/Packages
+/*.xcodeproj
+xcuserdata/
diff --git a/Graphs/Johnson's algorithm - Swift/readme.rtf b/Graphs/Johnson's algorithm - Swift/readme.rtf
deleted file mode 100644
index 80a8ebf..0000000
--- a/Graphs/Johnson's algorithm - Swift/readme.rtf	
+++ /dev/null
@@ -1,6 +0,0 @@
-
-Swift library that implements the Jonhson Cycle algorithm to find circuits in a directed graph
-
-Original Author : Frank Meyer (Java implementation)
-
-Wikipedia: "https://en.wikipedia.org/wiki/Johnson's_algorithm"
diff --git a/Package.swift b/Package.swift
new file mode 100644
index 0000000..ec04e3b
--- /dev/null
+++ b/Package.swift
@@ -0,0 +1,28 @@
+// swift-tools-version:5.1
+// The swift-tools-version declares the minimum version of Swift required to build this package.
+
+import PackageDescription
+
+let package = Package(
+    name: "JohnsonsAlgo",
+    products: [
+        // Products define the executables and libraries produced by a package, and make them visible to other packages.
+        .library(
+            name: "JohnsonsAlgo",
+            targets: ["JohnsonsAlgo"]),
+    ],
+    dependencies: [
+        // Dependencies declare other packages that this package depends on.
+        // .package(url: /* package url */, from: "1.0.0"),
+    ],
+    targets: [
+        // Targets are the basic building blocks of a package. A target can define a module or a test suite.
+        // Targets can depend on other targets in this package, and on products in packages which this package depends on.
+        .target(
+            name: "JohnsonsAlgo",
+            dependencies: []),
+        .testTarget(
+            name: "JohnsonsAlgoTests",
+            dependencies: ["JohnsonsAlgo"]),
+    ]
+)
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..73aa984
--- /dev/null
+++ b/README.md
@@ -0,0 +1,12 @@
+# JohnsonsAlgo
+
+Swift library that implements the Jonhson Cycle algorithm to find circuits in a directed graph
+Wikipedia: "https://en.wikipedia.org/wiki/Johnson's_algorithm"
+
+Original Author: Frank Meyer (Java implementation)  
+Swift Adaption: Marc Matta  
+Swift Package Manager Adaption: Klaus Kneupner  
+
+Known issues: sometimes the algo will end in a recursive loop, depending on the sequence of nodes provided. Details yet unknown. 
+
+
diff --git a/Graphs/Johnson's algorithm - Swift/AdjacencyList.swift b/Sources/JohnsonsAlgo/AdjacencyList.swift
similarity index 74%
rename from Graphs/Johnson's algorithm - Swift/AdjacencyList.swift
rename to Sources/JohnsonsAlgo/AdjacencyList.swift
index 7d5a612..0abcdd6 100644
--- a/Graphs/Johnson's algorithm - Swift/AdjacencyList.swift	
+++ b/Sources/JohnsonsAlgo/AdjacencyList.swift
@@ -8,6 +8,9 @@
 
 import Foundation
 
+public typealias AdjacencyMatrix = Array<Array<Bool>>
+//public typealias AdjacencyList = Array<Array<Int>>
+
 /**
  * Calculates the adjacency-list for a given adjacency-matrix.
  *
@@ -16,7 +19,7 @@ import Foundation
  * @version 1.0, 26.08.2006
  *
  */
-@objc public class AdjacencyList : NSObject {
+public class AdjacencyList {
     /**
      * Calculates a adjacency-list for a given array of an adjacency-matrix.
      *
@@ -28,18 +31,18 @@ import Foundation
      * that are direct successornodes of the node.
      */
     class func getAdjacencyList( adjacencyMatrix: Array<Array<Bool>>) -> Array<Array<Int>> {
-        var list = [Array<Int>](count: adjacencyMatrix.count, repeatedValue: [])
+        var list = [Array<Int>](repeating: [], count: adjacencyMatrix.count)
         
-        for var i = 0; i < adjacencyMatrix.count; ++i {
+        for i in 0..<adjacencyMatrix.count {
             var v = [Int]()
-            for var j = 0; j < adjacencyMatrix[i].count; ++j {
+            for j in 0..<adjacencyMatrix[i].count{
                 if (adjacencyMatrix[i][j]) {
                     v.append(j)
                 }
             }
             
-            list[i] = [Int](count:v.count, repeatedValue: 0)
-            for var j = 0; j < v.count; ++j {
+            list[i] = [Int](repeating: 0, count:v.count)
+            for j in 0..<v.count {
                 let in_ = v[j]
                 list[i][j] = in_
             }
@@ -47,4 +50,4 @@ import Foundation
         
         return list;
     }
-}
\ No newline at end of file
+}
diff --git a/Graphs/Johnson's algorithm - Swift/ElementaryCyclesSearch.swift b/Sources/JohnsonsAlgo/ElementaryCyclesSearch.swift
similarity index 73%
rename from Graphs/Johnson's algorithm - Swift/ElementaryCyclesSearch.swift
rename to Sources/JohnsonsAlgo/ElementaryCyclesSearch.swift
index f87d85a..66cf74c 100644
--- a/Graphs/Johnson's algorithm - Swift/ElementaryCyclesSearch.swift	
+++ b/Sources/JohnsonsAlgo/ElementaryCyclesSearch.swift
@@ -8,6 +8,13 @@
 
 import Foundation
 
+public typealias Matrix<Element> = Array<Array<Element>>
+
+public enum GraphErrors: Error {
+    case algoIssue
+    case missingObject
+}
+
 /**
 * Searchs all elementary cycles in a given directed graph. The implementation
 * is independent from the concrete objects that represent the graphnodes, it
@@ -33,15 +40,15 @@ import Foundation
 *
 */
 
-@objc public class ElementaryCyclesSearch : NSObject {
+open class ElementaryCyclesSearch<Element> {
     /** List of cycles */
-    private var cycles : Array<Array<AnyObject>>?
+    private var cycles : Array<Array<Element>>?
     
     /** Adjacency-list of graph */
     private var adjList : Array<Array<Int>>
     
     /** Graphnodes */
-    private var graphNodes : Array<AnyObject>
+    private var graphNodes : Array<Element>
     
     /** Blocked nodes, used by the algorithm of Johnson */
     private var blocked : Array<Bool>?
@@ -60,9 +67,9 @@ import Foundation
     * build sets of the elementary cycles containing the objects of the original
     * graph-representation
     */
-    init(matrix: Array<Array<Bool>>, graphNodes: Array<AnyObject>) {
+    public init(matrix: Array<Array<Bool>>, graphNodes: Array<Element>) {
         self.graphNodes = graphNodes;
-        self.adjList = AdjacencyList.getAdjacencyList(matrix);
+        self.adjList = AdjacencyList.getAdjacencyList(adjacencyMatrix: matrix);
     }
     
     /**
@@ -71,27 +78,30 @@ import Foundation
     *
     * @return List::List::Object with the Lists of the elementary cycles.
     */
-    func getElementaryCycles() -> Array<Array<AnyObject>> {
-        self.cycles = Array<Array<AnyObject>>()
-        self.blocked = [Bool](count:self.adjList.count, repeatedValue:false)
-        self.B = [Array<Int>](count: self.adjList.count, repeatedValue: [])
+    open func getElementaryCycles() throws -> Array<Array<Element>> {
+        if let result = cycles {
+            return result
+        }
+        self.cycles = Array<Array<Element>>()
+        self.blocked = [Bool](repeating:false, count:self.adjList.count)
+        self.B = [Array<Int>](repeating: [], count: self.adjList.count)
         self.stack = [Int]()
         
         let sccs = StrongConnectedComponents(adjList: self.adjList)
         var s = 0
         
         while(true) {
-            let sccResult = sccs.getAdjacencyList(s)
+            let sccResult = sccs.getAdjacencyList(node: s)
             if let result = sccResult {
                 let scc = result.adjList
                 s = result.lowestNodeId
-                for var j = 0; j<scc.count; ++j {
+                for j in 0..<scc.count{
                     self.blocked![j] = false
                     self.B![j] = [Int]()
                 }
                 
-                findCycles(s, s: s, adjList: scc)
-                s++
+                let _ = try findCycles(v: s, s: s, adjList: scc)
+                s = s + 1
             }else {
                 break
             }
@@ -110,33 +120,39 @@ import Foundation
     * connected component s is part of.
     * @return true, if cycle found; false otherwise
     */
-    func findCycles(v: Int, s: Int, adjList:Array<Array<Int>> ) -> Bool {
+    func findCycles(v: Int, s: Int, adjList:Array<Array<Int>> ) throws -> Bool {
         var f = false;
+        
+                
+        if stack?.contains(v) ?? false {
+            self.cycles = Array<Array<Element>>()
+            throw GraphErrors.algoIssue
+        }
         self.stack?.append(v)
         self.blocked![v] = true;
     
-        for var i = 0; i < adjList[v].count; ++i {
+        for i in 0..<adjList[v].count {
             let w = adjList[v][i]
             // found cycle
             if (w == s) {
-				var cycle = Array<AnyObject>()
-				for var j = 0; j < self.stack!.count; ++j {
+				var cycle = Array<Element>()
+				for j in 0..<self.stack!.count {
                     let index = self.stack![j]
                     cycle.append(self.graphNodes[index])
 				}
 				self.cycles?.append(cycle);
 				f = true;
             } else if (!self.blocked![w]) {
-                if (findCycles(w, s: s, adjList: adjList)) {
+                if (try findCycles(v: w, s: s, adjList: adjList)) {
                     f = true;
 				}
             }
         }
     
         if (f) {
-            unblock(v)
+            unblock(node: v)
         } else {
-            for var i = 0; i < adjList[v].count; ++i {
+            for i in 0..<adjList[v].count {
 				let w = adjList[v][i]
 				if (!self.B![w].contains(v)) {
                     self.B![w].append(v)
@@ -144,9 +160,9 @@ import Foundation
             }
         }
     
-        let indexToRemove = self.stack!.indexOf(v)
+        let indexToRemove = self.stack!.firstIndex(of: v)
         if let index = indexToRemove {
-            self.stack!.removeAtIndex(index)
+            self.stack?.remove(at: index)
         }
         return f
     }
@@ -161,10 +177,10 @@ import Foundation
         var Bnode = self.B![node]
         while (Bnode.count > 0) {
             let w = Bnode.first!
-            Bnode.removeAtIndex(0)
+            Bnode.remove(at:0)
             if (self.blocked![w]) {
-				self.unblock(w)
+                self.unblock(node: w)
             }
         }
     }
-}
\ No newline at end of file
+}
diff --git a/Graphs/Johnson's algorithm - Swift/SCCResult.swift b/Sources/JohnsonsAlgo/SCCResult.swift
similarity index 83%
rename from Graphs/Johnson's algorithm - Swift/SCCResult.swift
rename to Sources/JohnsonsAlgo/SCCResult.swift
index 871c6ac..74a9d2f 100644
--- a/Graphs/Johnson's algorithm - Swift/SCCResult.swift	
+++ b/Sources/JohnsonsAlgo/SCCResult.swift
@@ -8,7 +8,7 @@
 
 import Foundation
 
-@objc public class SCCResult : NSObject{
+public class SCCResult {
     var nodeIDsOfSCC : Set<Int>
     var adjList : Array<Array<Int>>
     var lowestNodeId : Int
@@ -17,10 +17,10 @@ import Foundation
         self.adjList = adjList
         self.lowestNodeId = lowestNodeId
         nodeIDsOfSCC = []
-        for var index = lowestNodeId; index < adjList.count; ++index {
+        for index in lowestNodeId..<adjList.count {
             if (adjList[index].count > 0) {
                 self.nodeIDsOfSCC.insert(index)
             }
         }
     }
-}
\ No newline at end of file
+}
diff --git a/Graphs/Johnson's algorithm - Swift/StrongConnectedComponents.swift b/Sources/JohnsonsAlgo/StrongConnectedComponents.swift
similarity index 78%
rename from Graphs/Johnson's algorithm - Swift/StrongConnectedComponents.swift
rename to Sources/JohnsonsAlgo/StrongConnectedComponents.swift
index ddeca83..4ba9600 100644
--- a/Graphs/Johnson's algorithm - Swift/StrongConnectedComponents.swift	
+++ b/Sources/JohnsonsAlgo/StrongConnectedComponents.swift
@@ -32,7 +32,7 @@ import Foundation
  * @version 1.1, 22.03.2009
  *
  */
-@objc public class StrongConnectedComponents :NSObject {
+public class StrongConnectedComponents {
     /** Adjacency-list of original graph */
     private var adjListOriginal : Array<Array<Int>>
     
@@ -78,25 +78,25 @@ import Foundation
      * connected component; null, if no such component exists
      */
     func getAdjacencyList(node:Int) -> SCCResult? {
-        self.visited = [Bool](count: self.adjListOriginal.count, repeatedValue: false)
-        self.lowlink = [Int](count: self.adjListOriginal.count, repeatedValue: 0)
-        self.number = [Int](count: self.adjListOriginal.count, repeatedValue: 0)
+        self.visited = [Bool](repeating: false, count: self.adjListOriginal.count)
+        self.lowlink = [Int](repeating: 0, count: self.adjListOriginal.count)
+        self.number = [Int](repeating: 0, count: self.adjListOriginal.count)
         self.stack = Array<Int>()
         self.currentSCCs = Array<Array<Int>>()
         
-        makeAdjListSubgraph(node)
+        makeAdjListSubgraph(node: node)
         
-        for var i = node; i<self.adjListOriginal.count; ++i {
+        for i in node..<self.adjListOriginal.count {
             if (!self.visited![i]) {
-                getStrongConnectedComponents(i)
+                getStrongConnectedComponents(root: i)
                 
                 let nodes = getLowestIdComponent()
-                if let n = nodes where (!n.contains(node) && !n.contains(node+1)) {
-                    return getAdjacencyList(node+1)
+                if let n = nodes, (!n.contains(node) && !n.contains(node+1)) {
+                    return getAdjacencyList(node: node+1)
                 } else {
-                    let adjacencyList = getAdjList(nodes)
+                    let adjacencyList = getAdjList(nodes: nodes)
                     if let ad = adjacencyList {
-                        for var j = 0; j<self.adjListOriginal.count; ++j {
+                        for j in 0..<self.adjListOriginal.count {
                             if (ad[j].count > 0){
                                 return SCCResult(adjList: ad, lowestNodeId: j)
                             }
@@ -117,19 +117,19 @@ import Foundation
      * @param node Node with lowest index in the subgraph
      */
     func makeAdjListSubgraph(node: Int) {
-        self.adjList = Array<Array<Int>>(count:self.adjListOriginal.count, repeatedValue:[])
+        self.adjList = Array<Array<Int>>(repeating:[], count:self.adjListOriginal.count)
         
-        for var i = node; i < self.adjList?.count; ++i {
+        for i in node..<self.adjList!.count {
             var successors = Array<Int>()
-            for var j = 0; j < self.adjListOriginal[i].count; ++j {
+            for j in 0..<self.adjListOriginal[i].count {
                 if self.adjListOriginal[i][j] >= node {
                     successors.append(self.adjListOriginal[i][j]);
                 }
             }
             
             if (successors.count > 0) {
-                self.adjList![i] = [Int](count:successors.count, repeatedValue:0)
-                for var j = 0; j < successors.count; ++j {
+                self.adjList![i] = [Int](repeating:0, count:successors.count)
+                for j in 0..<successors.count {
                     let succ = successors[j]
                     self.adjList![i][j] = succ
                 }
@@ -144,11 +144,11 @@ import Foundation
      * @return Vector::Integer of the scc containing the lowest nodenumber
      */
     func getLowestIdComponent() -> Array<Int>? {
-        var min = self.adjList?.count
+        var min = self.adjList!.count
         var currScc : Array<Int>?;
-        for var i = 0; i < self.currentSCCs?.count; ++i {
+        for i in 0..<self.currentSCCs!.count {
             let scc = self.currentSCCs![i]
-            for var j = 0; j < scc.count; ++j {
+            for j in 0..<scc.count {
                 let node = scc[j]
                 if (node < min) {
                     currScc = scc
@@ -167,13 +167,13 @@ import Foundation
     func getAdjList(nodes: Array<Int>?) -> Array<Array<Int>>?{
         var lowestIdAdjacencyList : Array<Array<Int>>?
         if let n = nodes {
-            lowestIdAdjacencyList =  [Array<Int>](count: self.adjList!.count, repeatedValue: [])
-            for var i = 0; i < lowestIdAdjacencyList!.count; ++i {
+            lowestIdAdjacencyList =  [Array<Int>](repeating: [], count: self.adjList!.count)
+            for i in 0..<lowestIdAdjacencyList!.count {
                 lowestIdAdjacencyList![i] = [Int]()
             }
-            for var i = 0; i < n.count; ++i {
+            for i in 0..<n.count{
                 let node = n[i]
-                for var j = 0; j < self.adjList![node].count; ++j {
+                for j in 0..<self.adjList![node].count {
                     let succ = self.adjList![node][j]
                     if n.contains(succ) {
                         lowestIdAdjacencyList![node].append(succ)
@@ -190,16 +190,16 @@ import Foundation
      * @param root node to start from.
      */
     func getStrongConnectedComponents(root: Int) {
-        self.sccCounter++
+        self.sccCounter = self.sccCounter + 1
         self.lowlink![root] = self.sccCounter
         self.number![root] = self.sccCounter
         self.visited![root] = true
         self.stack!.append(root)
         
-        for var i = 0; i < self.adjList![root].count; ++i {
+        for i in 0..<self.adjList![root].count {
             let w = self.adjList![root][i];
             if (!self.visited![w]) {
-                self.getStrongConnectedComponents(w)
+                self.getStrongConnectedComponents(root: w)
                 self.lowlink![root] = min(lowlink![root], lowlink![w])
             } else if (self.number![w] < self.number![root]) {
                 if (self.stack!.contains(w)) {
@@ -214,7 +214,7 @@ import Foundation
             var scc = [Int]()
             repeat {
                 next = self.stack!.last!
-                self.stack!.removeAtIndex(stack!.count - 1)
+                self.stack!.remove(at:stack!.count - 1)
                 scc.append(next)
             } while (self.number![next] > self.number![root])
             // simple scc's with just one node will not be added
@@ -224,11 +224,11 @@ import Foundation
         }
     }
     
-    class func test() {
-        var nodes = [String](count: 10, repeatedValue: "")
-        var adjMatrix = [[Bool]](count: 10, repeatedValue: [Bool](count: 10, repeatedValue: false));
+    class func test() throws {
+        var nodes = [String](repeating: "", count: 10)
+        var adjMatrix = [[Bool]](repeating: [Bool](repeating: false, count: 10), count: 10);
         
-        for var i = 0; i < 10; ++i {
+        for i in 0..<10 {
             nodes[i] = "Node " + String(i);
         }
         
@@ -245,12 +245,12 @@ import Foundation
         adjMatrix[8][6] = true;
         adjMatrix[6][1] = true;
         
-        let ecs = ElementaryCyclesSearch(matrix: adjMatrix, graphNodes: nodes)
-        let cycles = ecs.getElementaryCycles()
-        for var i = 0; i<cycles.count; ++i {
+        let ecs = ElementaryCyclesSearch(matrix: adjMatrix, graphNodes: nodes as Array<AnyObject>)
+        let cycles = try ecs.getElementaryCycles()
+        for i in 0..<cycles.count {
             let cycle = cycles[i]
             var representation = ""
-            for var j = 0; j<cycle.count; ++j {
+            for j in 0..<cycle.count {
                 let node = cycle[j]
                 if j < cycle.count - 1 {
                     representation += node as! String + " -> "
@@ -261,4 +261,4 @@ import Foundation
             print(representation + "\n")
         }
     }
-}
\ No newline at end of file
+}
diff --git a/Tests/JohnsonsAlgoTests/JohnsonsAlgoTests.swift b/Tests/JohnsonsAlgoTests/JohnsonsAlgoTests.swift
new file mode 100644
index 0000000..0c862b1
--- /dev/null
+++ b/Tests/JohnsonsAlgoTests/JohnsonsAlgoTests.swift
@@ -0,0 +1,27 @@
+import XCTest
+@testable import JohnsonsAlgo
+
+final class JohnsonsAlgoTests: XCTestCase {
+    func testBigExampleFromVithanco() throws {
+        // This is an example of a functional test case.
+        // Use XCTAssert and related functions to verify your tests produce the correct
+        // results.
+       // XCTAssertEqual(JohnsonsAlgo.text, "Hello, World!")
+        
+        let bigMatrix = [[false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false, true, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, true, false, false, false, false, false, false, true, true, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, true, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, true, false, false, false, false, false, false, false, true, true, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false], [false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, true, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false, true, false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false, true], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, true, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, true, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false, false]]
+        let elements = Array(1...74)
+        let ecs = ElementaryCyclesSearch(matrix: bigMatrix, graphNodes: elements)
+        let result = try ecs.getElementaryCycles()
+        XCTAssertEqual(result.count, 1000)
+        
+    }
+    
+    func testSmall() throws {
+        let matrix = [[false, false, false, false, false, false, false, false, false, false], [false, false, false, true, false, false, false, false, false, false], [false, false, false, false, false, true, true, false, false, false], [false, false, false, false, false, false, false, false, true, false], [false, false, true, false, false, false, false, true, false, false], [false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, false, false], [false, false, false, false, false, false, false, false, true, false], [false, false, false, false, false, false, false, false, false, true], [true, false, false, false, true, false, false, false, false, false]]
+        let elements = Array(1...10)
+        let ecs = ElementaryCyclesSearch(matrix: matrix, graphNodes: elements)
+        let result = try ecs.getElementaryCycles()
+        XCTAssertEqual(result.count, 1)
+    }
+
+}
diff --git a/Tests/JohnsonsAlgoTests/StrongComponentTest.swift b/Tests/JohnsonsAlgoTests/StrongComponentTest.swift
new file mode 100644
index 0000000..a9ca01d
--- /dev/null
+++ b/Tests/JohnsonsAlgoTests/StrongComponentTest.swift
@@ -0,0 +1,94 @@
+//
+//  StrongComponentTest.swift
+//  JohnsonsAlgoTests
+//
+//  Created by Klaus Kneupner on 07/05/2022.
+//
+
+
+import XCTest
+@testable import JohnsonsAlgo
+
+final class StrongComponentTests: XCTestCase {
+
+    func buildEmptyGraph(n: Int) -> (AdjacencyMatrix, Array<String>) {
+        var nodes = [String](repeating: "", count: n)
+        let adjMatrix = [[Bool]](repeating: [Bool](repeating: false, count: n), count: n);
+        
+        for i in 0..<n {
+            nodes[i] = "Node " + String(i);
+        }
+        return (adjMatrix,nodes)
+    }
+    
+    func testTarjan() throws {
+        var (adjMatrix,nodes) = buildEmptyGraph(n: 10)
+  
+        
+        adjMatrix[0][1] = true;
+        adjMatrix[1][2] = true;
+        adjMatrix[2][0] = true;
+        adjMatrix[2][6] = true;
+        adjMatrix[3][4] = true;
+        adjMatrix[4][5] = true;
+        adjMatrix[4][6] = true;
+        adjMatrix[5][3] = true;
+        adjMatrix[6][7] = true;
+        adjMatrix[7][8] = true;
+        adjMatrix[8][6] = true;
+        adjMatrix[6][1] = true;
+        
+        let ecs = ElementaryCyclesSearch(matrix: adjMatrix, graphNodes: nodes as Array<AnyObject>)
+        let cycles = try ecs.getElementaryCycles()
+        for i in 0..<cycles.count {
+            let cycle = cycles[i]
+            var representation = ""
+            for j in 0..<cycle.count {
+                let node = cycle[j]
+                if j < cycle.count - 1 {
+                    representation += node as! String + " -> "
+                }else {
+                    representation += node as! String
+                }
+            }
+            print(representation + "\n")
+        }
+    }
+    
+    // from: https://en.wikipedia.org/wiki/Strongly_connected_component
+    func testWikiExample () throws {
+        var (adjMatrix,nodes) = buildEmptyGraph(n: 8)
+        adjMatrix[0][1] = true
+        adjMatrix[1][2] = true
+        adjMatrix[1][4] = true
+        adjMatrix[1][5] = true
+        adjMatrix[2][3] = true
+        adjMatrix[2][6] = true
+        adjMatrix[3][2] = true
+        adjMatrix[3][7] = true
+        adjMatrix[4][0] = true
+        adjMatrix[4][5] = true
+        adjMatrix[5][6] = true
+        adjMatrix[6][5] = true
+        adjMatrix[7][6] = true
+        adjMatrix[7][3] = true
+
+        let ecs = ElementaryCyclesSearch(matrix: adjMatrix, graphNodes: nodes)
+        let cycles = try ecs.getElementaryCycles()
+        for i in 0..<cycles.count {
+            let cycle = cycles[i]
+            var representation = ""
+            for j in 0..<cycle.count {
+                let node = cycle[j]
+                if j < cycle.count - 1 {
+                    representation += node + " -> "
+                }else {
+                    representation += node
+                }
+            }
+            print(representation + "\n")
+        }
+        XCTAssertEqual(cycles.count,3 )
+       
+    }
+}
diff --git a/Tests/JohnsonsAlgoTests/XCTestManifests.swift b/Tests/JohnsonsAlgoTests/XCTestManifests.swift
new file mode 100644
index 0000000..a3932d4
--- /dev/null
+++ b/Tests/JohnsonsAlgoTests/XCTestManifests.swift
@@ -0,0 +1,9 @@
+import XCTest
+
+#if !canImport(ObjectiveC)
+public func allTests() -> [XCTestCaseEntry] {
+    return [
+        testCase(JohnsonsAlgoTests.allTests),
+    ]
+}
+#endif
diff --git a/Tests/LinuxMain.swift b/Tests/LinuxMain.swift
new file mode 100644
index 0000000..c9c922d
--- /dev/null
+++ b/Tests/LinuxMain.swift
@@ -0,0 +1,7 @@
+import XCTest
+
+import JohnsonsAlgoTests
+
+var tests = [XCTestCaseEntry]()
+tests += JohnsonsAlgoTests.allTests()
+XCTMain(tests)