//Average1.java
// Class average program with counter-controlled repetition
  import java.util.Scanner;
  public class Average1 {
  public static void main( String args[] )
  {
  int total, // sum of grades
  gradeCounter, // number of grades entered
  grade, // grade value
  average; // average of all grades
  // Initialization Phase
  total = 0;
  gradeCounter = 1;
  Scanner input = new Scanner(System.in); // Processing Phase
  while ( gradeCounter <= 10 ) { // loop 10 times
System.out.println("Enter grade as integer:");
  grade = input.nextInt();
  total = total + grade;
  gradeCounter = gradeCounter + 1;
  }
  // Termination Phase
  average = total / 10; // integer division will truncate result
  System.out.println("Class average is " + average); // display average of exam grades
  }}

//Average2.java
// Class average program with sentinel-controlled repetition
import java.util.Scanner;
    public class Average2 { 
public static void main( String args[] )
    {
    int gradeCounter, // number of grades entered
    gradeValue, // grade value
    total; // sum of grades
    double average; // average of all grades  
// Initialization phase 
total = 0;
gradeCounter = 0;  
// Processing phase
// prompt for input and read grade from user
Scanner input = new Scanner(System.in);
System.out.print("Enter Integer Grade or -1 to Quit");
gradeValue = input.nextInt();
while ( gradeValue != -1 ) {
    total = total + gradeValue;
    gradeCounter = gradeCounter + 1;
    System.out.print("Enter Integer Grade or -1 to Quit");
    gradeValue = input.nextInt();
    }
// Termination phase
if ( gradeCounter != 0 ) {
    average = (double) total / gradeCounter;
    System.out.println("Class average is " + average);
    }
    else
    System.out.println("No grades were entered");
    }
    }  

  
//Analysis.java
    // Analysis of examination results.
    import java.util.Scanner;
    public class Analysis {
    public static void main( String args[] )
  { 
int passes = 0, // number of passes
    failures = 0, // number of failures
    student = 1, // student counter
    result; // one exam result
    Scanner input = new Scanner(System.in); // user-entered value
    String output; // output string
// process 10 students; counter-controlled loop
    while ( student <= 10 ) {
    System.out.println("Enter result (1=pass,2=fail)" );
    result = input.nextInt();
    if ( result == 1 ) passes = passes + 1;
    else failures = failures + 1;
    student = student + 1;
    }
    // termination phase
    output = "Passed: " + passes + "\nFailed: " + failures;
    if( passes > 8 )
    output = output + "\nRaise Tuition";
    System.out.println("Analysis of Examination Results:\n" + output);
    }
    }
  

  
//Increment.java
    // Preincrementing and postincrementing
    public class Increment {
    public static void main( String args[] )
    {
    int c;
    c = 5;
    System.out.println( c ); // print 5
    System.out.println( c++ ); // print 5 then postincrement
    System.out.println( c ); // print 6
    System.out.println(); // skip a line
    c = 5;
    System.out.println( c ); // print 5
    System.out.println( ++c ); // preincrement then print 6
    System.out.println( c ); // print 6
    }
  }