Improving the Prompt

With the value "0" as the sentinel, if that value occurs in the list to be added, it can be skipped without any problem (since skipping it affects the sum the same way as adding it in.)

Here is the interesting part of the program again, with some additions to make the user prompt more "user friendly:"

    int count = 0;

    // get the first value
    System.out.println( "Enter first integer (enter 0 to quit):" );
    inputData  = userin.readLine();
    value      = Integer.parseInt( inputData );

    while ( value != 0 )    
    {
      //add value to sum
      sum = sum + value;

      //increment the count
      __________________

      //get the next value from the user
      System.out.println( "Enter the " + 
          (count+1) + "th integer (enter 0 to quit):" );
      inputData  = userin.readLine();
      value      = Integer.parseInt( inputData );
      
    }

    System.out.println( "Sum of the "  + count + " integers: " + sum );
  }
}

When this modified program is run, the user dialog should look something like the following:

C:\users\default\JavaLessons\chap18>java addUpNumbers

Enter first integer (enter 0 to quit):
12
Enter the 2th integer (enter 0 to quit):
-3
Enter the 3th integer (enter 0 to quit):
4
Enter the 4th integer (enter 0 to quit):
-10
Enter the 5th integer (enter 0 to quit):
0
Sum of the 4 integers: 3

Soon we will add additional statements to correct the dubious grammar in the second and third prompt.