You are given an n x n 2D matrix representing an image, rotate the image by 90 degrees (clockwise).
You have to rotate the image in-place, which means you have to modify the input 2D matrix directly. DO NOT allocate another 2D matrix and do the rotation.
Example 1:
Input: matrix = [[1,2,3],[4,5,6],[7,8,9]] Output: [[7,4,1],[8,5,2],[9,6,3]]
Example 2:
Input: matrix = [[5,1,9,11],[2,4,8,10],[13,3,6,7],[15,14,12,16]] Output: [[15,13,2,5],[14,3,4,1],[12,6,8,9],[16,7,10,11]]
Constraints:
//先让矩阵对称，然后水平轴对称 1 2 3 变成 1 4 7 变成 7 4 1 4 5 6 2 5 8 8 5 27 8 9 3 6 9 9 6 3 class Solution { public void rotate(int[][] matrix) { for(int i = 0; i < matrix.length; i++){ for(int j = i; j < matrix[0].length; j++){ int temp = matrix[i][j]; matrix[i][j] = matrix[j][i]; matrix[j][i] = temp; } } for(int i =0 ; i < matrix.length; i++){ for(int j = 0; j < matrix.length / 2; j++){ int temp = matrix[i][j]; matrix[i][j] = matrix[i][matrix.length-1-j]; matrix[i][matrix.length-1-j] = temp; } } } }
标签：Rotate,matrix,48,int,Image,++,length,temp,image From： https://www.cnblogs.com/MarkLeeBYR/p/16865323.html