Question

我的代码编译得很好，但是当我运行它时出现以下错误：

线程“main”中的异常java.lang.ArrayIndexOutOfBoundsException：0 在Sudoku。（Sudoku.java:20）在Test.main（Test.java:7）

代码如下：

主要测试类：

public class Test {
    public static void main(String[] args) {
        Sudoku puzzle;

        int[][] entries = {{1,0,0,0},{0,0,0,3},{0,0,4,0},{0,4,0,0}};
        puzzle = new Sudoku(2,2,entries);

        boolean somethingChanged=true;
        while(somethingChanged) {
            somethingChanged=false;
            System.out.println(puzzle);

            for (int i=0; i<puzzle.size; i++)
                for(int j=0; j<puzzle.size; j++)
                    if(puzzle.oneOption(i, j)!=puzzle.EMPTY) {
                        // exactly one value can be filled in at location i,j
                        // do this now, and record that something has changed
                        // compared to the previous iteration of the while loop
                        puzzle.setValue(i,j,puzzle.oneOption(i,j));
                        somethingChanged=true;
                    }
            }

        // if oneOption is implemented correctly, the puzzle is now solved!
        System.out.println(puzzle);
    }
}

和我未注释的Sudoku Class：

class Sudoku {

    int cellHeight, cellWidth, size,EMPTY = 0;
    int [][] sudGrid = new int[cellHeight * cellWidth][cellHeight * cellWidth];
    int [][] cellGrid = new int [cellHeight][cellWidth];

    public Sudoku(int a, int b){
        cellHeight = a;
        cellWidth = b;
        size = cellHeight*cellWidth;
    }

    public Sudoku(int a, int b, int array[][]){
        cellHeight = a;
        cellWidth = b;
        size = cellHeight*cellWidth;
        for(int i = 0; i<size; i++){
            for(int j = 0; j<size; j++){
                int temp = array[i][j];
                sudGrid[i][j] = temp;
            }
        }
    }

    public Sudoku(){
        cellHeight = 3;
        cellWidth = 3;
        size = cellHeight*cellWidth;
        for(int i = 0; i<size; i++)
            for(int j = 0; j<size; j++)
                sudGrid[i][j] = 0;
    }

    public void setValue(int r,int c, int v){
        sudGrid[r][c] = v;
    }

    public int getValue(int r, int c){
        return sudGrid[r][c];
    }

    public void clear(int r, int c){
        sudGrid[r][c] = EMPTY;
    }

    public String toString(){
        String message = "";
        for(int i = 0; i<size; i++){
           for(int j = 0; j<size; j++){
               message = message + sudGrid[i][j];
               if (j == cellWidth){
                   message = message + " ";
               }
            }
            message = message + "\n";
        }
        return message;
    }

    public int oneOption(int r, int c){
         return 1;
    }
}

很抱歉，我知道这是很多代码要在屏幕上显示，但我没有在阵列上做过很多，更不用说二维了。我知道我的oneOption()方法目前什么也没做，我只是需要它来编译，但错误在哪里，是

int temp = array[i][j];
sudGrid[i][j] = temp;

和

int[][] entries = {{1,0,0,0},{0,0,0,3},{0,0,4,0},{0,4,0,0}};
puzzle = new Sudoku(2,2,entries);

现在我假设条目数组声明的位置是正确的，因为这是我的讲师为我们设置的代码，我们只设计了Sudoku类。我试图使条目数组的值，进入sudGrid数组，我假设我做得正确，但我得到异常错误，

任何想法？

Answer 1

您将Sudoku.size设置为拼图中的整个单元格数，然后尝试读取那么多行和列。您只需迭代到列数和行数。

Answer 2

您的subgrid被定义为零长度二维数组，因此您无法在其中放置任何内容。

见这里：

int cellHeight, cellWidth, size,EMPTY = 0;
int [][] sudGrid = new int[cellHeight * cellWidth][cellHeight * cellWidth];

默认情况下，

cellHeight和cellWidth初始化为零，然后您创建一个new int[0*0][0*0]数组。

将构造函数更改为以下内容：

public Sudoku(int a, int b, int array[][]){
    cellHeight = a; // Changing these two instance variables will *NOT*
    cellWidth = b;  // retrofit your subGrid to a new size.
    size = cellHeight*cellWidth;
    subGrid = new int[size][size];
    for(int i = 0; i<size; i++){
        for(int j = 0; j<size; j++){
            int temp = array[i][j];
            sudGrid[i][j] = temp;
        }
    }
}

程序编译，但运行时数组超出界限？

2 个答案: