题目描述:
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?
思路:先将行顺序reverse,然后再对每个处于下三角区域的元素rotate。
代码:
void Solution::rotate(vector<vector<int> > &matrix) { reverse(matrix.begin(),matrix.end()); for(int i = 0;i < matrix.size();i++) for(int j = 0;j < matrix.size() - i;j++) { int temp = matrix[j][i]; matrix[j][i] = matrix[i][j]; matrix[i][j] = temp; } }
原文:http://blog.csdn.net/yao_wust/article/details/42143319