Compile and run the program. It is not complete, but it should run correctly with the first half of the data. Always compile and run a program-in-progress as soon as you can. Catch design flaws and bugs as early as you can.
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.*;
import java.util.Scanner;
public class TestGroups
{
public static void main ( String[] args ) throws IOException
{
int value; // the value of the current integer
// Prompt for and open the input file
Scanner user = new Scanner( System.in );
System.out.print("File name? ");
String fileName = user.next().trim();
Scanner scan = new Scanner( new File(fileName) );
// Group "A"
//
int sizeA; // the number of students in group "A"
int sumA = 0; // the sum of scores for group "A"
sizeA = scan.nextInt();
int count = 0; // initialize count
while ( count < sizeA )
{
value = scan.nextInt();
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"
sizeB = scan.nextInt();
count = 0; // initialize count
while ( count < sizeB )
{
value = scan.nextInt();
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" );
scan.close();
}
}
Is it a mistake to declare the variables sizeB and sumB in the
middle of the program?