```
public class Solution {
public void Rotate(int[,] matrix) {
int n = matrix.GetUpperBound(0);
for (int i = 0; i <= n / 2 ; i++){
for (int j = i; j < n - i; j++){
int temp = matrix[i, j];
matrix[i,j] = matrix[n - j, i];
matrix[n - j, i] = matrix[n - i, n - j];
matrix[n - i, n - j] = matrix[j, n - i];
matrix[j, n - i] = temp;
}
}
}
}
```