参考
时间复杂度: O ( n 2 ) O(n^2) O(n2)
空间复杂度: O ( 1 ) O(1) O(1)
class Solution {
public void rotate(int[][] matrix)
{
int n = matrix.length;
for(int i = 0; i < n/2; i++)
for(int j = 0; j < (n+1)/2; j++)
{
int t = matrix[i][j];
matrix[i][j] = matrix[n-1-j][i];
matrix[n-1-j][i] = matrix[n-1-i][n-1-j];
matrix[n-1-i][n-1-j] = matrix[j][n-1-i];
matrix[j][n-1-i] = t;
}
}
}