Problem: Sort an Array of 0s, 1s, and 2s

Given an array/list ARR consisting of integers where each element is either 0, 1, or 2, your task is to sort this array in increasing order.

Input:

The input starts with an integer ‘T’ representing the number of test cases. 
For each test case:
The first line contains a positive integer ‘N’, denoting the number of elements in the array.
The second line contains ‘N’ space-separated integers, which are the elements of the array.

Output:

For each test case, output the sorted array of ‘N’ space-separated integers on a new line.

Example:

Input:
2
4
0 2 1 1
5
2 1 0 0 1
Output:
0 1 1 2
0 0 1 1 2
Explanation:

For the first test case, the sorted array is [0, 1, 1, 2].
For the second test case, the sorted array is [0, 0, 1, 1, 2].

Constraints:

  • 1 ≤ T ≤ 100
  • 1 ≤ N ≤ 5000
  • 0 ≤ ARR[i] ≤ 2
  • Time limit: 1 sec

Note:

You are not required to print anything; the output handling has already been managed. Simply implement the function to sort the array.
AnswerBot
4mo

Sort an array of 0s, 1s, and 2s in increasing order.

  • Use a three-pointer approach to sort the array in a single pass.

  • Initialize three pointers for 0, 1, and 2 values and iterate through the array.

  • Swap ...read more

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