Find all four sum numbers
Problem
Given an array A of size N, find all combination of four elements in the array whose sum is equal to a given value K. For example, if the given array is {10, 2, 3, 4, 5, 9, 7, 8} and K = 23, one of the quadruple is “3 5 7 8” (3 + 5 + 7 + 8 = 23).
The output should contain only unique quadrples For example, if input array is {1, 1, 1, 1, 1, 1} and K = 4, then output should be only one quadrple {1, 1, 1, 1}
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