Average - Chapter 8

<html xmlns = "http://www.w3.org/1999/xhtml">
   <head>
      <title>Class Average Program</title>

      <script type = "text/javascript">
         <!--
         var total,          // sum of grades
             gradeCounter,   // number of grades entered
             gradeValue,     // grade value
             average,        // average of all grades
             grade;          // grade typed by user

         // Initialization Phase
         total = 0;          // clear total
         gradeCounter = 1;   // prepare to loop

         // Processing Phase
         while ( gradeCounter <= 3 ) {  // loop 10 times

            // prompt for input and read grade from user
            grade = window.prompt( "Enter integer grade:", "0" );

            // convert grade from a String to an integer
            gradeValue = parseInt( grade );

            // add gradeValue to total
            total = total + gradeValue;

            // add 1 to gradeCounter
            gradeCounter = gradeCounter + 1;
         }

         // Termination Phase
         average = total / 3;  // calculate the average

         // display average of exam grades
         document.writeln(
            "<h1>Class average is " + average + "</h1>" );
         // -->
      </script>

   </head>
   <body>
      <p>Click Refresh (or Reload) to run the script again</p>
   </body>
</html>