48. Rotate Image

Posted 2020-10-08 鸵鸟

class Solution {
    public void rotate(int[][] matrix) {
        int n=matrix.length;
        for(int i=0;i<n;i++)
            for(int j=i+1;j<n;j++)
                swap(matrix,i,j,j,i);
        for(int i=0;i<n;i++)
        {
            int l=0;
            int r=n-1;
            while(l<r)
            {
                swap(matrix,i,l,i,r);
                l++;
                r--;
            }
        }
    }
    private void swap(int[][] matrix, int i1, int j1, int i2, int j2){
        int tmp=matrix[i1][j1];
        matrix[i1][j1]=matrix[i2][j2];
        matrix[i2][j2]=tmp;
    }
}