Codility Demo Test - Java Solution

Codility-demo.java

// 100% marks solution for the github demo test
// Find an index in an array such that its prefix sum equals its suffix sum.
class Solution {
    public int solution(int[] A) {
        if(A.length == 0){
            return -1;
        }
        long leftSum = 0;
        long rightSum = getSum(A);

        for (int i = 0; i < A.length ; i++) {
            if(leftSum == rightSum - A[i]){
                return i;
            }
            leftSum = leftSum + A[i];
            rightSum = rightSum - A[i];
        }
        return -1;
    }


    public long getSum(int[] A){
        long sum = 0;
        for (int i  :A){
            sum = sum + i;
        }
        return sum;
    }


    public static void main(String[] args) {
        System.out.println(new Solution().solution(new int[]{-1, 3, -4, 5, 1, -6, 2, 1}));
    }
}