更改矩形二维数组中的值答案

【问题标题】：Changing value in rectangular two dimensional array更改矩形二维数组中的值
【发布时间】：2012-12-04 20:30:23
【问题描述】：

我正在创建一个非常基本的战舰程序来娱乐，我在我的矩形二维数组中更改值时遇到了问题。本质上，在这个二维数组中放置了五艘“船”。然后用户输入一个整数来查看他们是否命中或未命中。我希望输出显示带有猜测数字的数组，用X 表示未命中，0 表示命中。当area[i][j] 的值等于t 的值到0 或X 时，我无法更改它。我是java新手，所以我正在努力学习。任何帮助，将不胜感激。提前谢谢你。

import java.util.*;
public class battleship {

    //Rudimentary Battleship game
    public static void main(String[] args) {
        System.out.println(" Hello and welcome to a basic version of Battleship.");
        System.out.println(" The objective of this game is to sink all five ships located on the grid listed below.");
        System.out.println(" Follow the prompt located underneath the grid ");
        final int ROWS = 10;
        final int COLS = 10;
        int sum = 0;
        int [][] area = { {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},
                  {41,42,43,44,45,46,47,48,49,50},
                  {51,52,53,54,55,56,57,58,59,60},
                  {61,62,63,64,65,66,67,68,69,70},
                  {71,72,73,74,75,76,77,78,79,80},
                  {81,82,83,84,85,86,87,88,89,90},
                  {91,92,93,94,95,96,97,98,99,100} };

        for(int i=0; i < area.length; i++) {
            for (int j=0; j < area[i].length; j++) {


              if(area[i][j] < 10) 
                System.out.print("   "+(area[i][j])+" ");  
              else if(area[i][j] < 100) 
                System.out.print("  "+(area[i][j])+" ");
              else 
                System.out.print(" "+(area[i][j])+" ");
            }
          System.out.println("");
        }

    Scanner input = new Scanner(System.in);{
    System.out.println("Enter attack integer:");
    int t;
    while(true){
    t = input.nextInt();

    if ((t == 41) || (t == 42) || (t == 43)){
    System.out.println("Hit - Destroyer");}

    if ((t == 80) || (t == 90) || (t == 100)){
        System.out.println("Hit - Submarine");}


    if((t == 52) || (t == 62) || (t== 72) || (t == 82) || (t == 92)){
        System.out.println ("Hit - Aircraft Carrier");}

    if((t == 15) || (t == 16) || (t == 17) || (t == 18)){
        System.out.println ("Hit - Battleship");}

    if((t == 1) || (t == 2)){
        System.out.println ("Hit - PT Boat");}
    else{
        System.out.println ("Miss");
    }
    System.out.println("You have fired at:" + t);
    int w = 0;
    for(int i=0; i < area.length; i++) {
        for (int j=0; j < area[i].length; j++) {

            if (area[i][j] == t)

          if(area[i][j] < 10) 
            System.out.print("   "+(area[i][j])+" ");  
          else if(area[i][j] < 100) 
            System.out.print("  "+(area[i][j])+" ");
          else 
            System.out.print(" "+(area[i][j])+" ");
        }
      System.out.println("");
    }

        }
        }
    }
}

【问题讨论】：

要更改 [i, j] 的值，只需执行 area[i][j] = "whatever";
不是你的问题，但你可以用两个 for 循环更好地初始化你的二维数组“区域”，而不是手动输入。
1 2 3 4 5 6 7 8 9 10 11 12 13 14 ... 100 这是当前的输出。假设用户猜测“1”，我需要将“1”处的位置更改为 0 表示命中，X 表示未命中。在打印出上述输出的其余部分时。如：X 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 ... 100
感谢您的回复。我用布尔值重写了它。容易得多，我正在寻找什么。谢谢！

标签： java arrays for-loop multidimensional-array

【解决方案1】：

使用面向对象会更好。这是一个帮助您入门的框架：

public class Cell {
  private boolean ship = false;
  private boolean hit = false;

  public boolean getHit() {
    return hit;
  }
  public void setHit(boolean hit) {
    this.hit = hit;
  }
}

然后

public class Board() {
  public static final int SIZE = 10;
  private Cell[][] board;

  public Board() {
    board  = new Cell[SIZE][SIZE];
    for(int i = 0; i < 10; i++)
      for(int j = 0; j < 10; j++)
        board[i][j] = new Cell();

  public boolean getHit(int x, int y) {
    if(x < 0 || x >= SIZE || y < 0 || y >= SIZE) throw new BattleshipException("You queried a cell that doesn't exist!");
    return board[x][y].getHit();
  }
  // etc etc.
}

充实你需要的所有方法，在需要时添加字段，这样会更好！

【讨论】：

【解决方案2】：

这很简单，修改你的代码：

if ((t == 41) || (t == 42) || (t == 43)){
    System.out.println("Hit - Destroyer");
    area[i][j] = "X";
}
if ((t == 80) || (t == 90) || (t == 100)){
    System.out.println("Hit - Submarine");
    area[i][j] = "X";
}
if((t == 52) || (t == 62) || (t== 72) || (t == 82) || (t == 92)){
    System.out.println ("Hit - Aircraft Carrier");
    area[i][j] = "X";
}

if((t == 15) || (t == 16) || (t == 17) || (t == 18)){
    System.out.println ("Hit - Battleship");
    area[i][j] = "X";
}
if((t == 1) || (t == 2)){
    System.out.println ("Hit - PT Boat");
    area[i][j] = "X";
}
else{
    System.out.println ("Miss");
    area[i][j] = "O";
}

注意：请注意，数组的索引为 0，因此您的船位与您设置网格的方式不完全对应。即 area[4][1] 不是“41”。您似乎对列而不是行正确地执行了此操作（在驱逐舰的情况下）。如果船在 area[4][0]、area[4][1]、area [4][2]，if 语句应该检查 31、32、33。实际上，最好将位置标记为 00、01、02、...、97、98、99，以便索引与数字相对应。

【讨论】：