算法练习-回型矩阵

package Code1;

public class Code1_8回型矩阵 {


    static int length=8;
    static int value=1;
    static int[][] snake=new int[length][length];
    static Direction lastDirection=Direction.Right;
    static enum Direction{
        Right,Down,Left,Up;
    }


    public static void main(String[] args) {
        initialArray();
        print(snake);

    }
    private static void initialArray() {
        int row=0,col=0;
        for(int c=0;c<length*length;c++){
            snake[row][col]=value;
            lastDirection=findDirection(row,col);
            switch(lastDirection){
                case Right:
                    col++;
                    break;
                case Down:
                    row++;
                    break;
                case Left:
                    col--;
                    break;
                case Up:
                    row--;
                    break;
                default:
                    System.out.println("error");
            }
            value++;
        }

    }
    private static Direction findDirection(int row, int col) {
        Direction direction =lastDirection;
        switch(direction){
        case Right:{
            if((col==length-1)||(snake[row][col+1]!=0)){
                direction=direction.Down;
            }
            break;
        }
        case Down:{
            if((row==length-1)|| snake[row+1][col]!=0){
                direction=direction.Left;
            }
            break;
        }
        case Left:{
            if((col==0)||snake[row][col-1]!=0){
                direction=direction.Up;
            }
            break;
        }
        case Up:{
            if(snake[row-1][col]!=0){
                direction=direction.Right;
            }
            break;
        }
        }
        return direction;
    }
    private static void print(int[][] ary) {

        for(int i=0;i<ary.length;i++){
            for(int j=0;j<ary.length;j++){
                System.out.printf("%-3d",ary[i][j]);
            }
            System.out.println();
        }
    }
}

运行结果：