최대 연속 서브 그룹

public int MaxSubArray(int[] A, int n) {
        int maxSum = A[0];
        int currSum;
        for (int i = 0; i < n; i++) {
            for (int j = i; j < n; j++) {
                currSum = 0;
                for (int k = i; k <= j; k++) {
                    currSum += A[k];
                }
                if (currSum > maxSum) {
                    maxSum = currSum;
                }
            }
        }
        return maxSum;
    }

public int MaxAddSub(int[] a, int from, int to) {
        if (to == from) {
            return a[from];
        }

        int middle = (from + to) / 2;
        int m1 = MaxAddSub(a, from, middle);
        int m2 = MaxAddSub(a, middle+1, to);

        int left = a[middle];
        int now = a[middle];
        for (int i = middle-1; i >= from; i--) {
            now += a[i];
            left = max(left, now);
        }
        int right = a[middle+1];
        now = a[middle+1];
        for (int i = middle+2; i <= to; i++) {
            now += a[i];
            right = max(right, now);
        }
        int m3 = left + right;
        return max(max(m1, m2), m3);
    }

public int MaxAddSub2(int[] a) {
        int result = a[0];
        int sum = a[0];
        for (int i = 1; i < a.length; i++) {
            if (sum > 0) {
                sum += a[i];
            } else {
                sum = a[i];
            }
            if (sum > result) {
                result = sum;
            }
        }
        return result;
    }