ArrayOutofBoundary in Simple While Loop

Dear Friends:

The if statement in the while loop Line 50 is always wrong. I don't see anything wrong in it. If a pair of same numbers are put in the array, it runs well. If there is no such a pair the array is out of boundary. Could you see and fix the problem?

Thank you very much and the best regards!

John

Code :

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import java.io.*;
import java.math.*;
import cs1.Keyboard;
public class Try{
 public static void main(String[] args){
 
 int i, limit = 11;
  BigInteger[]C = new BigInteger[limit];
  C[1] = new BigInteger("1004");
  C[2] = new BigInteger("1000");
  C[3] = new BigInteger("1124");
  C[4] = new BigInteger("1034");
  C[5] = new BigInteger("1035");
  C[6] = new BigInteger("1023");
  C[7] = new BigInteger("1001");
  C[8] = new BigInteger("1101");
  C[9] = new BigInteger("1122");
  C[10] = new BigInteger("1114");
 
  System.out.println(" They are sorted as below:\n");
  BigInteger min = new BigInteger("0");
  BigInteger temp = new BigInteger("0");
  int j,minindex;
  for( i = 1; i< limit; i++ )
  {
   min = C[i];
   minindex = i;
   for(j = i+1; j < limit; j++ )
    if( C[j].compareTo(min) < 0 )  
    {
      min = C[j];
      minindex = j;
    }
 
    if( min.compareTo(C[i]) < 0 )
    {
      temp = C[i];
      C[i] = min;
      C[minindex] = temp;
     }
   }  
  for( i = 1; i < limit; i++ )
  System.out.println(" C["+i+"] = "+C[i]);
 
 System.out.println(" Stop where same numberw occur:\n");
 i = 0;
 while( i < limit )
 {
     i++;
     if(C[i].equals(C[i-1]))
     {
       System.out.println(" C["+i+"] = C["+(i-1)+" = "+C[i]);
       break;
     }
     System.out.println(" C["+i+"] = "+C[i]);
   }
  System.out.println(" Done.");
 }
}

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I didn't really give the code a good look but my first was at the array and it started with 1, normally a array starts at 0, and I saw the code:

Code :

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for( i = 1; i < limit; i++ )

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wich I think may be a problem. Try

Code :

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for( i = 1; i <= limit; i++ )

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Thank you Bryan. I don't have problem with that line. If you copy and paste the whole code on Source Editor, the problem is on Line 50: if (C[ i ].equals( C[ i - 1 ] ). Nothing seems to be wrong here, but it is so after it is run.

Regards.

John

Quote:

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while( i < limit )
{
i++;

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What happens here if i = limit-1

Quote:

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Originally Posted by Norm

What happens here if i = limit-1

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Norm hit the nail on the head. You increment i before you actually use i, so

Code :

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while ( i < limit ){//when  i = limit - 1
i++;
//now i = limit. C[11] is out of bounds of the array

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Why not just use a for loop rather than a while loop?

Dear Copeg, Norm, and Bryan:

I tried while( i < ( limit - 1 )) and it works! Thank you very much indeed for your clever suggestion! Have a nice day!

Regards.

John

hello, delete the i++ in the while loop and use while( i++ < limit ) instead.