[LeetCode] Rotate Image

標籤：java   leetcode   

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：先沿著主對角線交換矩陣內的數字，然後沿中間列交換。

public class Solution {    public void rotate(int[][] matrix) {    int rc = matrix.length;        for(int i=0;i<rc;i++){        for(int j=0;j<i;j++){        int temp = matrix[i][j];        matrix[i][j] = matrix[j][i];        matrix[j][i] = temp;        }        }                for(int j =0;j<rc/2;j++){        for(int i =0;i<rc;i++){        int temp = matrix[i][j];        matrix[i][j] = matrix[i][rc-1-j];        matrix[i][rc-1-j] = temp;        }        }    }}

[LeetCode] Rotate Image