[Dogstopper]

If I break it down, will that help?
1st:

          *        
         ***  
        *****       
      *********

Do that part with one for loop.

2nd:

        *****   
   *    *****     * 
  **    *****     **     
 *******     ********    
********     ********* 

See the pattern? You may have to use if statements in this one...

Then do it in reverse!

[cfoley]

Are you allowed to use arrays? Have you been taught about them yet?

[jane010794]

this one is not an executable class...

/**
*The Fraction class
*A template for a fraction that has the form numerator/denominator
*/
public class Fraction {
// data members
private int numerator; // holds the numerator of this fraction
private int denominator; // holds the denominator of this fraction
/**
*Constructs a fraction with numerator=0 and denominator = 1
*This constructor allows a Fraction with an equivalent numeric value of zero to
*be created… This becomes the default constructor (since it has no arguments)…
* Example of usage: Fraction f = new Fraction();
**/
public Fraction() {
numerator = 0;
denominator = 1;
}
/**
* This constructor creates a Fraction with the specified whole number as its initial value…
* Example of usage: Fraction f = new Fraction(10);
*/
public Fraction(int wholeNumVal) {
this.numerator = wholeNumVal;
denominator = 1;
}
/*
Alternative version of the constructor above, implemented by calling the
constructor defined below, using the this reference variable…
public Fraction(int wholeNumVal) {
this(wholeNumVal, 1);
}
*/
/**
*This constructor creates a Fraction using the explicit numerator and denominator values…
*Example of usage: Fraction f = new Fraction(5, 2);
*/
public Fraction(int numerator, int denominator) {
this.numerator = numerator; // the keyword this may be omitted
this.denominator = denominator; // the keyword this may be omittted
}
/**
*Accessor/Getter Method
*Returns the value of the numerator of this fraction
**/
public int getNumerator(){
return numerator;
}
/**
*Accessor/Getter Method
*Returns the value of the denominator of this fraction
**/
public int getDenominator(){
return denominator;
}
/**
*Mutator/Setter Method
*Sets the value of the numerator of this fraction to n
**/
public void setNumerator(int n){
numerator=n;
}
/**
*Mutator/Setter Method
*Sets the value of the denominator of this fraction to d
**/
public void setDenominator(int d){
denominator=d;
}
/**
*Returns a string form of the fraction following the format numerator/denominator
**/
public String toString(){
if(denominator==1)
	return(numerator + "");
	else
	return (numerator + "/" + denominator );
}
/**
*Returns the reduced(simpliest) form of this fraction
**/
public Fraction reduce(){
Fraction r= new Fraction(); // construct a fraction
int gCF = computeGCF(); // determine the greatest common factor of numerator and denominator
int newN= numerator/gCF; //compute newN, the numerator of the simpliest form of this fraction
//compute newD, the denominator of the simpliest form of this fraction
int newD = denominator/gCF;
r.setNumerator(newN); // set the numerator of the simpliest form to newN
r.setDenominator(newD);// set the denominator of the simpliest form to newD
return r; // return the simpliest form of this fraction
}
// Compuets the greastest common factor of the numerator and denominator
private int computeGCF(){
int gCF=1;
int lesser = 1;
boolean found=false;
lesser = computeLesser(numerator, denominator);
for (int candidate= lesser; (candidate >= 1 && !found); candidate--){
if (numerator%candidate == 0 && denominator%candidate==0){
found = true;
gCF= candidate;
}
}
return gCF;
}
//Returns the lesser integer between n1 and n2
private int computeLesser(int n1, int n2){
int lesser=0;
if (n1<n2)
lesser = n1;
else
lesser = n2;
return lesser;
}
/**
*Returns the sum of this fraction and another fraction g
**/
public Fraction sum(Fraction g){
Fraction s=new Fraction();
int den = denominator * g.getDenominator();
int num = den/denominator*numerator + den/g.getDenominator()*g.getNumerator();
s.setNumerator(num);
s.setDenominator(den);
return s.reduce();
}
/**
*returns the difference of this fraction and another fraction g
**/
public Fraction difference(Fraction g){
Fraction d=new Fraction();
int den = denominator * g.getDenominator();
int num = den/denominator*numerator - den/g.getDenominator()*g.getNumerator();
d.setNumerator(num);
d.setDenominator(den);
return d.reduce();
}
/**
*Return the product of this fraction and another fraction g
**/
public Fraction product(Fraction g){
Fraction p=new Fraction();
int den = denominator * g.getNumerator();
int num = den/denominator*numerator * den/g.getDenominator()*g.getNumerator();
p.setNumerator(num);
p.setDenominator(den);
return p.reduce();
}
/**
*Return the quotient of this fraction and another fraction g
**/
public Fraction quotient(Fraction g){
Fraction q=new Fraction();
int den = denominator * g.getDenominator();
int num = den/denominator*numerator / den/g.getDenominator() *g.getNumerator();
q.setNumerator(num);
q.setDenominator(den);
return q.reduce();
}


} // end of Fraction class

and this one has an error and it is an executable class..

import java.util.Scanner;

public class TestFraction2{
	Scanner scan = new Scanner(System.in);

	public TestFraction2(){

	}

	public static void main(String[] args){

	   int choice;

       System.out.println("This program helps you perform arithmetic operations with fractions");
	   System.out.println("What do you want to do?");
	   System.out.println("1. Add fractions");
	   System.out.println("2. Subtract fractions");
	   System.out.println("3. Multiply fractions");
	   System.out.println("4. Divide fractions");
	   System.out.println("5. Reduce a fraction");
	   System.out.println("6. Quit");

	   do{

	   	System.out.println("Enter your choice<1/2/3/4/5/6>:");
        choice = scan.nextInt();

        switch(choice){
        	case 1:Fraction sum();
        	       System.out.println("Sum = " + s.reduce);
        	       break;

        	case 2:Fraction difference();
        	       System.out.println("Difference = " + d.reduce);
        	       break;

            case 3:Fraction product();
        	       System.out.println("Product = " + p.reduce);
        	       break;

        	case 4:Fraction quotient();
        	       System.out.println("Quotient = " + q.reduce);
        	       break;

            case 5:Fraction reduce();
        	       System.out.println("Reduce = " + r);
        	       break;

        	case 6:System.out.println("Thank you for using my Program!");
        	       System.exit(0);

        default: System.out.println("Invalid choice! Enter again");
        }
	   }while(choice<=7);


		TestFraction2 myProgram;

		try{
			myProgram = new TestFraction2();
			myProgram.run();

		}catch (Exception e){
			System.out.println(e.getMessage());
		}
	}

	public void run(){
	   Fraction f1 = readFraction();
	   Fraction f2 = readFraction();
	   System.out.println(f1.toString());
	   System.out.println(f2);

	}

	public Fraction readFraction(){
		Fraction f;
		System.out.print("Enter a numerator: ");
		int num =  readInt();
		System.out.print("Enter a denominator: ");
		int den =  readInt();
        f = new Fraction(num, den);
		return f;
	}

   public int readInt(){
   	  int value=0;
   	  boolean noProblem = true;
     do {
      try {
   	    value = Integer.parseInt(scan.nextLine());
   	    noProblem = true;
      } catch (Exception e ){
      	System.out.println("You entered an invalid datum. Enter again: ");
      	noProblem = false;
      }

     } while (!noProblem);

   	  return value;
   }


}

it has an error in the switch case like in case 1: ';' expected

hoping can find a better code..

Edited by macosxnerd101: Please, .

[pbl]

A switch statement if constructed at compilation time
so it is built from CONSTANTS

   switch(value) {
      case 1:
        ....
        break;
      case 2:
        ....
        break;

it CANNOT be built at run time using a value returned by a method

    switch(value) {
       case method1();
         ....
         break;
       case method2();
         ....
         break;

Actually think about it.. what will you do if method1() and method2() return the SAME value ???