All Unique Permutations

You are given an array Arr consisting of N integers. Your task is to find all the unique permutations of the given array. For e.g if the array is {1, 1, 2}, the unique permutations of this array are {1, 1, 2}, {1, 2, 1}, {2, 1, 1}. Note that the total number of permutations of {1,1,2} is equal to 6 but out of those {1,1,2} and {1,2,1} occur twice.

Note:

1. There might be duplicates present in the array.
2. The order of the permutations in the output does not matter.
3. Do not use any kind of in-built library functions to find the answer.

Input Format:

The first line contains the integer N, denoting the size of the array.

The second line contains N space-separated integers denoting the array elements.

Output Format:

The output contains K lines, where each line contains N space-separated integers denoting one of the unique permutations of the given array.

Output for each test case must be in a separate line.

Note :

You do not need to print anything, it has already been taken care of. Just implement the given function.

Constraints:

1 <= N <= 6

Time Limit: 1 sec