Given a N x N 2D matrix Arr representing an image. Rotate the image by 90 degrees (anti-clockwise). You need to do this in place. Note that if you end up using an additional array, you will only receive partial score.
Example 1:
Input:
N = 3
Arr[][] = {{1, 2, 3}
{4, 5, 6}
{7, 8, 9}}
Output:
3 6 9
2 5 8
1 4 7
Explanation: The given matrix is rotated
by 90 degree in anti-clockwise direction.
Example 2:
Input:
N = 4
Arr[][] = {{1, 2, 3, 4}
{5, 6, 7, 8}
{9, 10, 11, 12}
{13, 14, 15, 16}}
Output:
4 8 12 16
3 7 11 15
2 6 10 14
1 5 9 13
Explanation: The given matrix is rotated
by 90 degree in anti-clockwise direction.
Your Task:
You don't need to read input or print anything. Your task is to complete the function rotate() which takes the 2D array of integers arr and n as parameters and returns void. You need to change the array itself.
Expected Time Complexity: O(N*N)
Expected Auxiliary Space: O(1)
Constraints:
1 ≤ N ≤ 1000
1 ≤ Arr[i][j] ≤ 1000

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