Java 2D-Array mit Benutzereingabe

Question

Ich fest auf ein Problem mit meinem Java-Programm in, wenn ich Zahlen eingeben wird Index Fehler außerhalb der Grenzen zurückgegeben. Die Linie ist die, an der sie sich verfängt.

arrayName[row][col] = holder; 

jede Hilfe bei der Ermittlung des Problems wäre am hilfreichsten. vollständiges Programm unter

package workfiles; 

    import java.util.*; 
    import java.util.Scanner; 

public class prob2 { 

// Do not modify this method 
public static void main(String[] args) { 

    try 
    { 
     int [][] iArray = enter2DPosArray(); 
     System.out.println("The original array values:"); 
     print2DIArray(iArray); 
     int [][] tArray = transposition(iArray); 
     System.out.println("The transposed array values:"); 
     print2DIArray(tArray); 
    } 

    catch (InputMismatchException exception) 
    { 
     System.out.println("The array entry failed. The program will now halt."); 
    } 

} 

    // A function that prints a 2D integer array to standard output 
    // It prints each row on one line with newlines between rows 
    public static void print2DIArray(int[][] output) { 

    } 

// A function that enters a 2D integer array from the user 
// It raises an InputMismatchException if the user enters anything other 
// than positive (> 0) values for the number of rows, the number of 
// columns, or any array entry 
public static int[][] enter2DPosArray() throws InputMismatchException { 

    int row=0; 
    int col=0; 
    int arow=0; 
    int acol=0; 
    int holder=0; 
    Scanner numScan = new Scanner(System.in); 

    while (row<=0){ 
     System.out.print("How many rows (>0) should the array have? "); 
     row = numScan.nextInt(); 
    } 

    while (col<=0){ 
     System.out.print("How many columns (>0) should the array have? "); 
     col = numScan.nextInt(); 
    } 
    int[][] arrayName = new int[row+1][col+1]; 

    while (arow < row) { 

     if (acol<=col) 
      System.out.println("Enter a positive (> 0) integer value: "); 
      holder = numScan.nextInt(); 
    // !!!line 66 begins right here!!! 
      arrayName[arow][acol] = holder; 
      acol ++; 

     if (acol>col) 
      acol=0; 
      arow ++; 
      System.out.println("Enter a positive (> 0) integer value: "); 
      holder = numScan.nextInt(); 
      arrayName[arow][acol] = holder; 
      acol ++; 



    } 
    //arrayName[i][j] 
    numScan.close(); 
    return arrayName; 
} 

public static int[][] transposition(int [][] arrayName) { 

    int r=0, c=0; 

    int[][] transpose = new int[r][c]; 
    for (int i = 0; i < r; i++) { 
     for (int j = 0; j < c; j++) { 
      transpose[i][j] = arrayName[j][i]; 
     } 
    } 
    return transpose; 
} 

} 

Answer 1

gibt diesen einen Versuch:

if (acol <= col) { 
     System.out.println("Enter a positive (> 0) integer value: "); 
     holder = numScan.nextInt(); 
     arrayName[arow][acol] = holder; 
     acol++; 
    } 
    if (acol > col) { 
     acol=0; 
     arow ++; 
     System.out.println("Enter a positive (> 0) integer value: "); 
     holder = numScan.nextInt(); 
     arrayName[arow][acol] = holder; 
     acol++; 
    } 

Answer 2

ich Eclipse an meinen Computer neu installiert und entfernt eine while-Schleife, die Werte auf Null gehalten Einstellung und änderte es eine statment wenn ja es nur einmal passiert, ich kann nicht erklären, wie oder warum das ein out of bounds Fehler ausgeführt wurde, aber das Programm funktioniert jetzt korrekt.

package workfiles; 



    import java.util.*; 
    import java.util.Scanner; 

    public class hw2 { 

    // Do not modify this method 
    public static void main(String[] args) { 

    try 
    { 
     int [][] iArray = enter2DPosArray(); 
     System.out.println("The original array values:"); 
     print2DIArray(iArray); 
     int [][] tArray = transposition(iArray); 
     System.out.println("The transposed array values:"); 
     print2DIArray(tArray); 
    } 

    catch (InputMismatchException exception) 
    { 
     System.out.println("The array entry failed. The program will now halt."); 
    } 

} 

    // A function that prints a 2D integer array to standard output 
    // It prints each row on one line with newlines between rows 
    public static void print2DIArray(int[][] output) { 
    int iArray[][]; 

     for (int row = 0; row < iArray.length; row++) { 
      for (int column = 0; column < iArray[row].length; column++) { 
       System.out.print(iArray[row][column] + " "); 
      } 
      System.out.println(); 
     } 
    } 



// A function that enters a 2D integer array from the user 
// It raises an InputMismatchException if the user enters anything other 
// than positive (> 0) values for the number of rows, the number of 
// columns, or any array entry 
public static int[][] enter2DPosArray() throws InputMismatchException { 

    int row=0; 
    int col=0; 
    int arow=0; 
    int acol=0; 
    int holder; 
    Scanner numScan = new Scanner(System.in); 

    while (row<=0){ 
     System.out.print("How many rows (>0) should the array have? "); 
     row = numScan.nextInt(); 
    } 

    while (col<=0){ 
     System.out.print("How many columns (>0) should the array have? "); 
     col = numScan.nextInt(); 
    } 
    int[][] iArray = new int[row][col]; 

    while (arow < row) { 

     while (acol < col) { 
      System.out.println("Enter a positive (> 0) integer value: "); 
      holder = numScan.nextInt(); 
      iArray[arow][acol] = holder; 
      acol++; 
     } 

    //this is where i replaced the while loop for the if statment, in the while loop it kept on resetting the acol value. there was no need to loop that part of the program.  

    if (acol >= col) { 
      acol = 0; 
      arow ++; 

     } 



    } 
    //arrayName[i][j] 
    numScan.close(); 
    return iArray; 
} 

public static int[][] transposition(int [][] iArray) { 

    int r=0, c=0; 

    int[][] transpose = new int[r][c]; 
    for (int i = 0; i < r; i++) { 
     for (int j = 0; j < c; j++) { 
      transpose[i][j] = iArray[j][i]; 
     } 
    } 
    return transpose; 
    } 

}