Massive Algorithms: Buttercola: LinkedIn: Find the balanced point of an unsorted array

Buttercola: LinkedIn: Find the balanced point of an unsorted array
Given a unsorted array, find the balanced point where the total sum of its left equals to the sum of its right. Return the index. If not exist, return -1.
e.g. [1, 2, 1, 3, 0]. Return 2

    public int findBalancedPoint(int[] nums) {

        if (nums == null || nums.length == 0) {

            return -1;

}

        int n = nums.length;

        int[] left = new int[n];

        int[] right = new int[n];

        // Step 1: get the sum of its left

        for (int i = 1; i < n; i++) {

            left[i] = left[i - 1] + nums[i - 1];

}

        // Step 2: get the sum of its right

        for (int i = n - 2; i >= 0; i--) {

            right[i] = right[i + 1] + nums[i + 1];

}

        // Step 3: compare left[i] and right[i]

        for (int i = 0; i < n; i++) {

            if (left[i] == right[i]) {

                return i;

}

}

        return -1;

}

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