Rearrange an array with O(1) extra space
Medium Accuracy: 54.65% Submissions: 37158 Points: 4

Given an array arr[] of size N where every element is in the range from 0 to n-1. Rearrange the given array so that arr[i] becomes arr[arr[i]].

 

Example 1:

Input:
N = 2
arr[] = {1,0}
Output: 0 1
Explanation: 
arr[arr[0]] = arr[1] = 0.
arr[arr[1]] = arr[0] = 1.

 

Example 2:

Input:
N = 5
arr[] = {4,0,2,1,3}
Output: 3 4 2 0 1
Explanation: 
arr[arr[0]] = arr[4] = 3.
arr[arr[1]] = arr[0] = 4.
and so on.

 

Your Task:
You don't need to read input or print anything. The task is to complete the function arrange() which takes arr and N as input parameters and rearranges the elements in the array in-place. 

 

Expected Time Complexity: O(N)
Expected Auxiliary Space: O(1)

 

Constraints:
1 <= N <= 107
0 <= Arr[i] < N

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Rearrange an array with O(1) extra space

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