for loop inside for loop

Question

I am trying to insert data to multidementional array, but 'for loop' inside for loop(inner 'for loop') not running (when i run the code inner loop not runnig only other 'for loop')you can clearly see that at result i attached with this quection.

Some code:

for(int s=0;s<=y;s++){  //y mean number of arrays, user can input any number for y in here y>=2
     int w=s+1;
     System.out.println("number of data for array"+" "+w+':');
     int night[][]=new int[s][x.nextInt()];
     for(int counter=0;counter<night.length;counter++){
         int m=counter+1;
         System.out.println("insert the number"+m+":");
         night[s][counter]=x.nextInt();

     }
}

I am still learning Java please tell me why this not working

This is the result when i run that code

how much Arrays:
4
number of data for array 1:
6
number of data for array 2:
7
insert the number1:
Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 1
    at practice.Multi_array_data_input.main(Multi_array_data_input.java:42)

*"not working"* is not a proper problem description, what exactly is not working? — luk2302, Jun 05 '17 at 12:33
Can you please elaborate on the "not working" part? ***How*** is it "not working"? Do you get build errors? Exceptions when running? Unexpected results? Please take some time to [read about how to ask good questions](http://stackoverflow.com/help/how-to-ask) and learn how to create a [Minimal, Complete, and Verifiable Example](http://stackoverflow.com/help/mcve). — Some programmer dude, Jun 05 '17 at 12:33
And today you just learned that Java and JavaScript are two different languages. — epascarello, Jun 05 '17 at 12:37
In the first iteration of the outer loop the value of `s` is zero. What happens when you create an array with zero elements? What valid indexes will it have? There are many other problems as well, but start thinking about this one. — Some programmer dude, Jun 05 '17 at 12:38
Possible duplicate of [What causes a java.lang.ArrayIndexOutOfBoundsException and how do I prevent it?](https://stackoverflow.com/questions/5554734/what-causes-a-java-lang-arrayindexoutofboundsexception-and-how-do-i-prevent-it) — Tom, Jun 05 '17 at 12:43

score 1 · Accepted Answer · answered Jun 05 '17 at 12:41

The problem is that you call a index in an array, which does not exists, because arrays in Java and JavaScript are zero-based. When you define an array with int[] array = new int[3] does this mean, that the indexes 0, 1, 2 are available. The index 3 is not part of the array. So to solve the problem you have to minimise the variable s by 1, when you call your night array.

for(int s=0;s<=y;s++){ // y mean number of arrays, user can input any number for y in here y>=2
    int w=s+1;
    System.out.println("number of data for array "+w+':');
    int night[][]=new int[s][x.nextInt()];
    for(int counter=0;counter<night.length;counter++){
        int m=counter+1;
        System.out.println("insert the number "+m+":");
        night[s - 1][counter]=x.nextInt();
    }
}

thanks...............a lot................:) – S.Sachith Jun 05 '17 at 12:43 — S.Sachith, Jun 05 '17 at 12:43

for loop inside for loop

1 Answers1