ReorderDataInLogFiles.java

package com.dbc;

import java.util.Arrays;

public class ReorderDataInLogFiles {
    class Pair {
        String log;
        int index;
        public Pair(String log, int index) {
            this.log = log;
            this.index = index;
        }
    }

    public int logCompare(Pair pair1, Pair pair2) {
        String log1 = pair1.log, log2 = pair2.log;
        int index1 = pair1.index, index2 = pair2.index;
        String[] split1 = log1.split(" ", 2);
        String[] split2 = log2.split(" ", 2);
        boolean isDigit1 = Character.isDigit(split1[1].charAt(0));
        boolean isDigit2 = Character.isDigit(split2[1].charAt(0));
        if (isDigit1 && isDigit2) return index1 - index2;
        if (!isDigit1 && !isDigit2) {
            int sc = split1[1].compareTo(split2[1]);
            if (sc != 0) return sc;
            return split1[0].compareTo(split2[0]);
        }
        return isDigit1 ? 1 : -1;
    }

    public String[] reorderLogFiles(String[] logs) {
        int length = logs.length;
        Pair[] arr = new Pair[length];
        for (int i = 0; i < length; i++) {
            arr[i] = new Pair(logs[i], i);
        }
        Arrays.sort(arr, (a, b) -> logCompare(a, b));
        String[] reordered = new String[length];
        for (int i = 0; i < length; i++) {
            reordered[i] = arr[i].log;
        }
        return reordered;
    }
}