[LeetCode] Rotate Image

You are given an n x n 2D matrix representing an image.

Rotate the image by 90 degrees (clockwise).

Follow up:

Could you do this in-place?

问题描述：给定一个n*n的二维矩阵，它代表的是一幅图片，将这个图片，也就是矩阵顺时针旋转90度。

我采用的方法和之前Spiral Matrix II类似，一圈一圈地向里面推进。然后用一个变量来作为中转。

class Solution {  
public:  
    void rotate(vector<vector<int> > &matrix) {  
        // IMPORTANT: Please reset any member data you declared, as  
        // the same Solution instance will be reused for each test case.  
        int n = matrix.size();  
  
        int temp = 0;  
        int i = 0, j = 0;  
        int start = 0, end = n-1;  
        int index = 0;  
        int width = 0;  
        width = n-1;  
        while(start < end) {  
            for(j = start; j < end; j++) {  
                temp = matrix[index][j];  
                matrix[index][j] = matrix[width-j][index];  
                matrix[width-j][index] = matrix[width-index][width-j];  
                matrix[width-index][width-j] = matrix[j][width-index];  
                matrix[j][width-index] = temp;  
            }  
            index++;  
            start++;  
            end--;  
        }  
    }  
};

补充：软件开发 , C++ ,