Four Sum Problem

You are given an array of integers and a target integer. Your task is to find all unique quadruplets [a, b, c, d] in the array that satisfy the equation:

\(a+b+c+d = \text{target}\)

Each quadruplet must be sorted in non-decreasing order and the solution set must not contain duplicate quadruplets.

Note: The order of the quadruplets in the output does not matter, but each quadruplet should be printed in non-decreasing order.

inputFormat

The input is read from standard input (stdin) and has the following format:

n target
num1 num2 ... numn

Here, the first line contains two integers: n (the number of elements in the array) and target (the target sum). The second line contains n space-separated integers representing the array.

outputFormat

Print all unique quadruplets found, one per line. Each quadruplet should be printed as four space-separated integers in non-decreasing order. If no quadruplet exists that satisfies the condition, output nothing.

## sample

6 0
1 0 -1 0 -2 2

-2 -1 1 2
-2 0 0 2
-1 0 0 1

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