/**
knakul853
https://leetcode.com/problems/rotate-image/discuss/18872/A-common-method-to-rotate-the-image
**/
class Solution {
public:
    void rotate(vector<vector<int>>& matrix) {

        int n = (int)matrix.size();

         for(int  i=0;i<(n)/2; i++ )
         {
             for(int j=0;j<(n+1)/2;j++ )
             {
                 int pre = matrix[i][j];

                 for(int k=0;k<4;k++)
                 {
                     int new_i = j;
                     int new_j = n-1-i;

                     int temp = matrix[new_i][new_j];
                     matrix[new_i][new_j] = pre;
                     pre = temp;

                     i = new_i;
                     j = new_j;
                 }
             }
         }

    }
};