EqualSumSubArrays.java

package Array;

public class EqualSumSubArrays {

    /**
     * @param arr - It is the array who's total sum is to be calculated.
     * @param n   - It is the length of the array.
     * @return - It returns the total sum of the array.
     */
    static int totalSum(int[] arr, int n) {
        int sum = 0;
        for (int i = 0; i < n; i++)
            sum += arr[i];
        return sum;
    }

    /**
     * @param a - It is the array under consideration
     * @return - It returns if the array 'a' has any two sub-arrays whose sums are
     * equal.
     */
    static boolean check(int[] a) {
        int n = a.length;
        int prefix = 0;
        int total_sum = totalSum(a, n);

        for (int num : a) {
            prefix += num;
            int suffix = total_sum - prefix;
            if (prefix == suffix)
                return true;

        }
        return false;
    }

    // Time Complexity - O(n), Auxiliary Space - O(1)
    public static void main(String[] args) {
        int[] a = {2, 3, -1, 8, 4};
        System.out.println(check(a));
    }
}