更改二维数组中的元素

Question

我要做的是生成一个15x15平方的“ - ”并接受用户输入坐标，然后将“ - ”替换为“x”，目前我的程序只是打印一条“ - ”的垂直线

import java.util.*;
public class GameOfLife
{
    public static void main(String[] args)
    {
        int[][] boardList = new int[15][15];
        Scanner myScanner = new Scanner(System.in);
        boolean done = false;
        do
        {
            System.out.println("1 - Add a being \n 2 - Show current board \n 3 - Show next generation \n 4 - Clear board \n 5 - Add preload pattern \n 6 - Exit");
            int choice = Integer.parseInt(myScanner.nextLine());
            if (choice == 1)
            {
                System.out.print("Enter the x coordinate: ");
                String answer = myScanner.nextLine();
                int xCoordinate = Integer.parseInt(answer);
                System.out.print("Enter the y coordinate: ");
                String answer2 = myScanner.nextLine();
                int yCoordinate = Integer.parseInt(answer2);
                for(int i = 0; i < 15; i++)
                {
                    for(int j = 0; j < 15; j++)
                    {
                        if(xCoordinate == i)
                        {
                            if(yCoordinate == j)
                            {
                                System.out.printf("x", boardList[i][j]);
                            }
                        }
                        else
                        System.out.printf("-", boardList[i][j]);
                        System.out.println();
                    }
                }
            }
        }
    }
}

Answer 1

在这里，你的工作......你需要把System.out.println(); 外循环以及放置

if(xCoordinate == i){
  if(yCoordinate == j){

一个条件......

 public static void main(String[] args) {
            int[][] boardList = new int[15][15];
            Scanner myScanner = new Scanner(System.in);
            boolean done = true;
            do {
                System.out
                        .println("1 - Add a being \n 2 - Show current board \n 3 - Show next generation \n 4 - Clear board \n 5 - Add preload pattern \n 6 - Exit");
                int choice = Integer.parseInt(myScanner.nextLine());
                if (choice == 1) {
                    System.out.print("Enter the x coordinate: ");
                    String answer = myScanner.nextLine();
                    int xCoordinate = Integer.parseInt(answer);
                    System.out.print("Enter the y coordinate: ");
                    String answer2 = myScanner.nextLine();
                    int yCoordinate = Integer.parseInt(answer2);
                    for (int i = 0; i < 15; i++) {
                        for (int j = 0; j < 15; j++) {
                            if (xCoordinate == i && yCoordinate == j) {
                                System.out.printf("x", boardList[i][j]);
                            } else
                                System.out.printf("-", boardList[i][j]);
                        }
                        System.out.println();
                    }
                }
            } while (done);

        }

//我改变编辑注释done真只是为了证明它的作品...

Answer 2

尝试这个

for(int i = 0; i < 15; i++)
{
    for(int j = 0; j < 15; j++)
    {
        if(xCoordinate == i && yCoordinate==j)
            System.out.printf("x", boardList[i][j]);
        else
            System.out.printf("-", boardList[i][j]);
    }
    System.out.println();
}

首先完成整行打印后，需要打印新行

Answer 3

如果我理解得很好，你想要一个用' - '初始化的二维数组，这样你就可以做到

int[][] boardList = new int[15][15];

for (int row = 0; row < 15; row ++)
    for (int col = 0; col < 15; col++)
        boardList[row][col] = '-';

然后，一旦您将用户数据存储在xCoordinate和Ycoordinate ，您就可以：

boardList[xCoordinate][Ycoordinate] = 'x';

Answer 4

你可以试试这段代码：

import java.util.Scanner;


public class StackOverflow 
{
    public static void main(String[] args)
    {
        int[][] boardList = new int[15][15];
        Scanner myScanner = new Scanner(System.in);
        boolean done = false;
        System.out.println("1 - Add a being \n 2 - Show current board \n 3 - Show next generation \n 4 - Clear board \n 5 - Add preload pattern \n 6 - Exit");
        int choice = Integer.parseInt(myScanner.nextLine());
        if (choice == 1)
        {
            System.out.print("Enter the x coordinate: ");
            String answer = myScanner.nextLine();
            int xCoordinate = Integer.parseInt(answer);
            System.out.print("Enter the y coordinate: ");
            String answer2 = myScanner.nextLine();
            int yCoordinate = Integer.parseInt(answer2);
            for(int i = 0; i < 15; i++)
            {
                for(int j = 0; j < 15; j++)
                {
                    if(xCoordinate == i)
                    {
                        if(yCoordinate == j)
                        {
                            System.out.printf("x", boardList[i][j]);
                        }
                        else
                        {
                            System.out.printf("-", boardList[i][j]);
                        }
                    }
                    else
                    {
                        System.out.printf("-", boardList[i][j]);
                    }

                }
                System.out.println();
            }
        }
    }
}