[Count] clockwise weekly print a matrix

As stated, a matrix print clockwise. For example, the input matrix:

1 2 3 4

5 6 7 8

9 10 11 12

13 14 15 16

Print out sequentially: 1 2. 4 8,121,615,141,395,671,110

Problem-solving ideas: Clockwise print, this matrix is thought of as a circle, a line regiment, starting at 1 draw, so roll up the line group, is not the case?

Is not that the famous rolling ball of algorithms Well! !

Yes, first printing 1234, and then roll over the matrix into a new matrix:

8 12 16

7 11 15

9 10 14

5 9 13

The second print 81216, and then roll over the matrix into a new matrix:

15 14 13

11 10 9

7 9 5

And so, oh friends, started working:

/**
 * @description: 顺时针打印一个矩阵
 *          例如输入矩阵：
 *              1  2  3  4
 *              5  6  7  8
 *              9  10 11 12
 *              13 14 15 16
 *          打印出:1 2 3 4 8 12 16 15 14 13 9 5 6 7 11 10
 * @author: JandMin
 * @create: 2019-05-24 09:26
 **/
public class ClockwisePrintMatrix {
    public static void main(String[] args) {
        int n = 6;
        int m = 7;
        int[][] matrix = getMatrix(n ,m);
        print(matrix);
        System.out.println("==========================");
        printClockwise(n,m,matrix);
    }

    /**
     * 顺时针打印
     * @param n 外层数组得长度
     * @param m 里层数组得长度
     * @param array 目标数组
     */
    private static void printClockwise(int n,int m,int[][] array){
        for(int j=0; j<m; j++){
            print(array[0][j]);
        }
        int[][] newArray = reverse(n,m,array);
        if(null == newArray || newArray.length <= 0){
            return;
        }
        printClockwise(newArray.length,newArray[0].length,newArray);
    }

    /**
     * 数组顺时针转90度，并且去掉第一个里层数组，变成一个新的数组
     * @param n 外层数组得长度
     * @param m 里层数组得长度
     * @param array 目标数组
     * @return
     */
    private static int[][] reverse(int n,int m,int[][] array) {
        if(n <=1){
            return null;
        }
        int[][] newArray = new int[m][n-1];
        int x = 0;
        int y = 0;
        for(int j=m-1; j>=0; j--){
            for(int i=1; i<n; i++){
                newArray[x][y++] = array[i][j];
            }
            x++;
            y = 0;
        }
        return newArray;
    }

    /**
     * 从1开始获取二维数组
     * @param n 外层数组得长度
     * @param m 里层数组得长度
     * @return
     */
    public static int[][] getMatrix(int n,int m){
        int[][] matrix = new int[n][m];
        int k = 1;
        for(int i=0; i<n; i++){
            for(int j=0; j<m; j++) {
                matrix[i][j] = k++;
            }
        }
        return matrix;
    }

    private static void print(int[][] array){
        for(int i=0; i<array.length; i++){
            for(int j=0; j<array[i].length; j++){
                print(array[i][j]);
            }
            System.out.println();
        }
    }
    private static void print(int num){
        System.out.print(num);
        if(num < 10){
            System.out.print("  ");
        } else {
            System.out.print(" ");
        }
    }
}

Execution results are as follows:

1 2 3 4 5 6 7
8 9 10 11 12 13 14
15 16 17 18 19 20 21
22 23 24 25 26 27 28
29 30 31 32 33 34 35
36 37 38 39 40 41 42
==========================
1 2 3 4 5 6 7 14 21 28 35 42 41 40 39 38 37 36 29 22 15 8 9 10 11 12 13 20 27 34 33 32 31 30 23 16 17 18 19 26 25 24

Of course, there are many solution would be more simple, welcome Daniel pointed out the error, or a comment posted more solution, the exchange! !

====== ======== method than problems

[Count] clockwise weekly print a matrix

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