Java学习-练习-Day01

题目来源：《疯狂Java讲义》

第一题

package study;

public class ArrayTest {
    public static void main (String[] args){
       int[] arr = {1,2,3,4,5,6,7,8,9};
        for (int i: arr ) {
            for (int j=1;j <= i;j++) {
                if(j > 1){System.out.print(',');}
                System.out.print(i+" X "+j+" = "+i*j);
            }
            System.out.print('\n');
        }
    }
}

第二题

package study;

public class ArrayTest {
    public static void main (String[] args){
        System.out.println("输入4");
        int num = 4;
        int line = num * 2 - 1;
        for(int i = 0;i < num;i++){
            for(int j = 0;j < line;j++){
                int count = i * 2 + 1;
                int space = (line - count) / 2;
                if(j >= space && j < (space + count)){
                    System.out.print('*');
                }else{
                    System.out.print(' ');
                }
            }
            System.out.print('\n');
        }
    }
}

第六题

package study;

import java.io.BufferedReader;
import java.io.InputStreamReader;

public class Gobang {
    private static int BOARD_SIZE = 15;
    private String[][] board;
    public void initBoard(){
        //初始化棋盘数组
        board = new String[BOARD_SIZE][BOARD_SIZE];
        //画出棋盘
        for(int i=0;i<BOARD_SIZE;i++){
            for (int j=0;j<BOARD_SIZE;j++){
                board[i][j] = "╋";
            }
        }
    }
    //在控制台输出棋盘
    public void printBoard(){
        //打印
        for (int i=0;i<BOARD_SIZE;i++){
            for(int j=0;j<BOARD_SIZE;j++){
                System.out.print(board[i][j]);
            }
            System.out.print('\n');
        }
    }
    public static void main (String[] args)throws Exception{
        Gobang gb = new Gobang();
        gb.initBoard();
        gb.printBoard();
        //键盘输入
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        String inputStr = null;
        while((inputStr = br.readLine()) != null){
            String[] posStrArr = inputStr.split(",");
            int xPos = Integer.parseInt(posStrArr[0]);
            int yPos = Integer.parseInt(posStrArr[1]);
            gb.board[yPos-1][xPos-1] = "●";
            gb.printBoard();
            System.out.println("请输入您下棋的坐标，以x,y的格式:");
        }
    }
}