leetCode 48.Rotate Image (旋转图像) 解题思路和方法

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?

思路:其实就是旋转数组,没有什么难度,代码如下:

public class Solution {
    public void rotate(int[][] matrix) {
    	int[][] a = new int[matrix.length][matrix.length];
    	//实现深拷贝
    	for(int i = 0; i < matrix.length; i++){
    		for(int j = 0; j < matrix.length;j++){
    			a[i][j] = matrix[i][j];
    		}
    	}
    	//数据旋转
        for(int i = 0; i < a[0].length; i++){
            int k = 0;
            for(int j = a.length-1; j >=0; j--){
                matrix[i][k++] = a[j][i];
                //System.out.print(a[j][i] + " ");
            }
            //System.out.println("");
        }
    }
}

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时间: 2024-10-08 06:30:49

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