Last Half

The last half of the program is nearly the same as the first, so it is a good idea to check that the first half works before going on. Here is the completed program:

import java.io.*;
class TestGroups
{
  public static void main ( String[] args ) throws IOException
  {
    String line;
    BufferedReader stdin = new BufferedReader( 
        new InputStreamReader( System.in ) );
    int value;     // the value of the current integer

    // Group "A"
    int sizeA;     // the number of students in group "A"
    int sumA = 0;  // the sum of scores for group "A"

    System.out.println("How many students in group A:");
    line   = stdin.readLine();
    sizeA  = Integer.parseInt( line.trim() );

    int count = 0; // initialize count

    while ( count < sizeA )
    {
      System.out.println("Enter a number:");
      line   = stdin.readLine();
      value  = Integer.parseInt( line.trim() );
      sumA  = sumA + value ; // add to the sum
      count = count + 1;     // increment the count
    }

    if ( sizeA > 0 )
      System.out.println( "Group A average: " + ((double) sumA)/sizeA );
    else
      System.out.println( "Group A  has no students" );
  
    // Group "B"
    int sizeB;     // the number of students in group "B"
    int sumB = 0;   // the sum of scores for group "B"

    System.out.println("How many students in group B:");
    line   = stdin.readLine();
    sizeB  = Integer.parseInt( line.trim() );

    count = 0; // initialize count

    while ( count < sizeB )
    {
      System.out.println("Enter a number:");
      line   = stdin.readLine();
      value  = Integer.parseInt( line.trim() );
      sumB  = sumB + value ; // add to the sum
      count = count + 1; // increment the count
    }

    if ( sizeB > 0 )
      System.out.println( "Group B average: " + ((double) sumB)/sizeB );
    else
      System.out.println( "Group B  has no students" );
  }
}

The two halves of the code are very similar.