数组 indexoutofboundsException:3

Question

无法弄清楚为什么我的int[][] totalOpenness = new int[n][n];array 不断超出范围异常：3。我对public static void openfactor(char[][] mazeValue, int n) 方法的计算工作正常；但是，我在openfactor(char[][] mazeValue, int n) 内的以下 2 行中遇到数组索引越界错误，我似乎永远无法通过我的整个数组，甚至无法接近。请帮忙！ :)

totalOpenness[i][j] = openness;
System.out.println("TOTAL OPENESS FOR : [" + i + "]" +"[" + j + "]  IS " +totalOpenness[i][j]);

import java.util.*;
public class Game {

    public static void main(String[] args) {
    Scanner kbd = new Scanner(System.in);
    System.out.println("ENTER A SINGLE INTEGER: ");
    int n = kbd.nextInt();
    char[][] mazeValue = new char[n + 1][n + 1];
    System.out.println("ENTER A PATH: ");
    for (int i = 0; i < mazeValue.length; i++) {
        for (int j = 0; j < mazeValue[i].length; j++) {
            if (i == 0 || j == 0 || i == n + 1 || j == n + 1)
                mazeValue[i][j] = 'X';
            else {
                mazeValue[i][j] = kbd.next().charAt(0);
            }
        }
    }
    printMaze(mazeValue);
    openfactor(mazeValue, n);
}
public static void printMaze(char mazeValue[][]) {
    System.out.println("MAZE");
    for (int i = 1; i < mazeValue.length; i++) {
        for (int j = 1; j < mazeValue[i].length; j++) {
            System.out.printf("%5c", mazeValue[i][j]);
        }
        System.out.printf("\n");
    }
}
public static void openfactor(char[][] mazeValue, int n){

       int[][] totalOpenness = new int[n][n];
       for(int i = 1; i<=n; i++)
       {  
           
           for(int j=1;j<=n;j++)
          {

              int count=0;
              int openness=0;

               if(mazeValue[i][j]=='X'){
                   System.out.println("tHIS IS AN X FOR : [" + i + "]" +"[" + j + "] IS -1 ");
                   count--;
               }

              else 
               {
               //YOU NEED TO VERIFY THAT J IS NOT OUT OF BOUND
               if( j-1>=1)
                    {
               if(mazeValue[i][j-1]=='O')
                        count++;
                    }
                      // System.out.println("cout: "+count);

                    if(i-1>=1 && j-1>=1)
                    {
                    if(mazeValue[i-1][j-1]=='O')
                        count++;
                    }
                     //  System.out.println("cout: "+count);
                     if(i-1>=1)
                    {
                    if(mazeValue[i-1][j]=='O')
                        count++;
                     }
                    //   System.out.println("cout: "+count);
                    if(j+1<=n)
                    {
                    if(mazeValue[i][j+1]=='O')
                        count++;
                    }
                     //  System.out.println("cout: "+count);
                    if(j+1<=n && i+1<=n)
                    {
                    if(mazeValue[i+1][j+1]=='O')
                        count++;
                    }
                    if (i+1<=n)
                    {
                    if(mazeValue[i+1][j]=='O')
                        count++;
                    }
                    //   System.out.println("cout: "+count);
                    if(j-1>=1 && i+1<=n)
                    {
                    if(mazeValue[i+1][j-1]=='O')
                        count++;
                    }
                    if(i-1>=1 && j+1<=n)
                    {
                    if(mazeValue[i-1][j+1]=='O')
                        count++;
                    }
            //}//eND OF iF CONDITION\
            }
            openness = openness +count;
            totalOpenness[i][j] = openness;
            System.out.println("TOTAL OPENESS FOR : [" + i + "]" +"[" + j + "]  IS " +totalOpenness[i][j]);
           
         }
      }
   
   }

Answer 1

看the documentation for ArrayIndexOutOfBoundsException：

抛出以指示已使用非法索引访问数组。索引为负数或大于或等于数组的大小。

您正在对 java 数组使用基于 1 的索引，这些数组使用基于 0 的索引 (Java Tutorials)：

for(int i = 1; i<=n; i++)
  for(int j=1;j<=n;j++)

将在i=n 处出现异常，因为totalOpenness[n][anynumber] 是无效的数组索引，这是因为它是用int[][] totalOpenness = new int[n][n] 声明的，所以元素索引是0, 1, ..., n-1。

将循环更改为：

for(int i = 0; i < n; i++)
  for(int j = 0; j < n; j++)

不幸的是，for 循环内的逻辑似乎也假设基于 1 的索引，因此您也必须更改它。