原地旋转正方形矩阵

public class test28 {
    public static void rotate(int[][] matrix){
        int a =0;
        int b =0;
        int c = matrix.length-1;
        int d = matrix[0].length-1;
        while (a < c){//由于是正方形，所以行越界列一定越界
            rotateEdge(matrix , a++ , b++ , c-- ,d--);
        }
    }

    public static void rotateEdge(int[][] m, int a, int b, int c,int d){
        int tmp = 0;
        for(int i =0 ; i < d-b ;i++){//有多少组次
            //m[a][b+i]上面一组
            //m[a+i][d]右边一组
            //m[c][d-i]下面一组
            //m[c-i][b]左边一组
            //然后不断组与组变换解决
            tmp = m[a][b+i];
            m[a][b+i] = m[c-i][b];
            m[c-i][b] = m[c][d-i];
            m[c][d-i] = m[a+i][d];
            m[a+i][d] =tmp;
        }
    }
}