Error in inverted Pascal triangle program

Hi everyone. I don´t know why the following error appears when I try to execute my program, so if anyone can help me please... xD

Source code:

import java.util.*;

public class pascal2 {

public static void main(String[] args) {

Scanner in = new Scanner(System.in);

int x = 0;

do {

System.out.print("How many values (1...13) ?");

x = in.nextInt();

} while ( x<1 || x>13 );

int y = (x*2)-1;

int [] a = new int [y];

int [][] b = new int [y][x];

int j = (x-1);

int k = y;

for ( x = 0 ; x <= j ; x++ ) {

for ( y = 0 ; y < k ; y++ ) {

if ( x == 0 ) {

if ( y == (((k+1)/2)-1) ) b[y][x] = 1;

else b[y][x] = 0;

}

else {

if ( y == 0 ) b[y][x] = b[y+1][x-1];

else {

if ( y == (k-1) ) b[y][x] = b[y-1][x-1];

else b[y][x] = b[y-1][x-1] + b[y+1][x-1];

}

}

}

}

for ( x = j ; x >= 0 ; x-- ) {

for ( y = 0 ; y <= k ; y++ ) {

if ( y == (k-1) ) {

if ( b[y][x] == 0 ) System.out.println(" ");

else System.out.println( b[y][x] );

}

else {

if ( b[y][x] == 0 ) System.out.print(" "); <-- line 43

else System.out.print( b[y][x] );

}

}

}

}

}

Error in cmd:

D:\>java pascal2

How many values (1...13) ?7

1 6 15 20 15 6 1

Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 13

at pascal2.main(pascal2.java:43)

Re: Error in inverted Pascal triangle program

Please use [**code**] tags [**/code**] when posting code.

I'm guessing here (as I don't read unformatted code), but you are accessing someArray[13] where someArray is only 13 elements long.

Arrays go from 0 to (arrayLength - 1).

Re: Error in inverted Pascal triangle program

I fixed it, thanks a lot (I knew arrays go from 0 to lenght-1, but you helped me remind it xD )

I didnt understand "", can you explain it some other way? because I dont want to botter anyone else with that, and I was hoping you could help me fix the spaces, because when the user selects a number of lines that contain numbers with more than one digit, the spaces go all wrong... and for you to help me you need to read the code xDDD

Re: Error in inverted Pascal triangle program

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