` ````
```

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Given four lists A, B, C, D of integer values, compute how many tuples `(i, j, k, l)`

there are such that `A[i] + B[j] + C[k] + D[l]`

is zero.

To make problem a bit easier, all A, B, C, D have same length of N where 0 ≤ N ≤ 500. All integers are in the range of -2^{28} to 2^{28} - 1 and the result is guaranteed to be at most 2^{31} - 1.

**Example:**

Input:A = [ 1, 2] B = [-2,-1] C = [-1, 2] D = [ 0, 2]Output:2Explanation:The two tuples are: 1. (0, 0, 0, 1) -> A[0] + B[0] + C[0] + D[1] = 1 + (-2) + (-1) + 2 = 0 2. (1, 1, 0, 0) -> A[1] + B[1] + C[0] + D[0] = 2 + (-1) + (-1) + 0 = 0

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