Programming Challenge 2: Fractions

[Lster]

So it seems I must pick the next challenge.

*Drum roll* This weeks challenge is... to implement a simple fractions library that can manipulate fractions in various ways. Probably, you will want to implement a class to store the fraction with a numerator and denominator. As usual, creativity, efficiency and elegance are weighed to decide the winner. Any language is welcome - and the elegance is subjective to that language.

The implementation must provide the following functions:

• It must have a function for making a new fraction, setting the numerator and denominator. For example, it could be called Fraction_Create.
• A function for multiplying two fractions, returning a new fraction as output. It could be called Fraction_Multiply.
• A function for printing the fraction, such as Fraction_Print. It can print the fraction as either a top heavy fraction or a mixed fraction.

Bonus features (for more points):

• A function for returning the reciprocal of a fraction.
• Functions for addition, subtraction and division (of fractions).
• The ability to simplify fractions and only ever returning fully simplified fractions from any of the functions listed will get you bonus points.
• A function to convert a fraction to an approximate decimal.
• A function to convert a decimal to an approximate fraction. Clever algorithms here will get you bonus points!

You can't use any fraction libraries already created - you must code them from scratch! A winner will be picked on Wednesday the fifth of March based on the above.

Good luck and if you have any question, post them here!
Lster

[insineratehymn]

Haha, I just had to write this program for my intro to C++ class...

Where do I submit it to?

[LaRoza]

Note, this was written as soon as I got up, and saw this thread. So it isn't the best, obviously, that I could do.

Updating
main.c:

#include <stdio.h>
#include <stdlib.h>
#include "fraction.h"

int main(int args,char*argv)
{
    Fraction x = newFraction(3,2);
    Fraction y = newFraction(5,7);
    Fraction z = getReciprocal(y);

    Fraction added = addFraction(x,y);
    Fraction subbed = subFraction(x,y);
    Fraction mult = multiplyFraction(x,y);
    Fraction div = divideFraction(x,y);


    printFraction(x,0);
    printFraction(y,0);
    printFraction(z,0);

    printFraction(x,1);
    printFraction(y,1);
    printFraction(z,1);

    printFraction(added,0);
    printFraction(subbed,0);
    printFraction(mult,0);
    printFraction(div,0);

    deleteFraction(x);
    deleteFraction(y);
    deleteFraction(z);
    deleteFraction(added);
    deleteFraction(subbed);
    deleteFraction(mult);
    deleteFraction(div);

    return 0;
} 

Output:

3/2
5/7
7/5
1 1/2
5/7
2 2/5
31/14
11/14
15/14
21/10

fraction.h

typedef struct
{
    int num;
    int denom;
} * Fraction;

Fraction addFraction(Fraction,Fraction);
Fraction divideFraction(Fraction,Fraction);
Fraction getReciprocal(Fraction);
Fraction multiplyFraction(Fraction,Fraction);
Fraction newFraction(int,int);
Fraction subFraction(Fraction,Fraction);

void deleteFraction(Fraction);
int getCommonDenom(Fraction,Fraction);
void printFraction(Fraction,int); 

fraction.c

#include <stdio.h>
#include <stdlib.h>
#include "fraction.h"
Fraction addFraction(Fraction f, Fraction f2)
{
    int commonDenom = getCommonDenom(f,f2);
    return newFraction(((commonDenom/f->denom) * f->num)+((commonDenom/f2->denom) * f2->num),commonDenom);
}

Fraction divideFraction(Fraction f, Fraction f2)
{
    Fraction temp = getReciprocal(f2);
    Fraction divideFraction = multiplyFraction(f,temp);
    deleteFraction(temp);
    return divideFraction;
}

Fraction subFraction(Fraction f, Fraction f2)
{
    int commonDenom = getCommonDenom(f,f2);
    return newFraction(((commonDenom/f->denom) * f->num)-((commonDenom/f2->denom) * f2->num),commonDenom);
}

Fraction getReciprocal(Fraction f)
{
    return newFraction(f->denom,f->num);
}

Fraction multiplyFraction(Fraction f,Fraction f2)
{
    return newFraction(f->num * f2->num,f->denom * f2->denom);
}

Fraction newFraction(int x,int y)
{
    Fraction f = malloc(sizeof(Fraction));
    f && y != 0 ? f->num = x, f->denom = y : printf("Error in init, denominator = %d numerator = %d",x,y);
    return f;
}


void deleteFraction(Fraction f)
{
    free(f);
}
int getCommonDenom(Fraction f, Fraction f2)
{
    return f->denom * f2->denom;
}
void printFraction(Fraction f,int mode)
{
    mode == 0 ? printf("%d/%d\n",f->num,f->denom) : f->denom == 1 ? printf("%d\n",f->num) : f->num > f->denom ? printf("%d %d/%d\n",f->num / f->denom,f->num - ((f->num / f->denom) * f->denom),f->denom) : printFraction(f,0);
} 

It is a mix of fulflilling the specs in the OP, rapid coding, and trying to confuse new C coders.

[Lster]

Very nice. How about add, subtract and canceling?

[LaRoza]

Very nice. How about add, subtract and canceling?

I haven't:

* eaten
* drank
* gotten fully dress
* read the paper
* looked for job (do it every day)

Finishing the library will have to wait. I have priorities (and coding this showed where some of them are)

(Note, anyone who doesn't see the point of pointers, read the code, and try to do it without pointers)

Updated to include other operations, sorry, nothing fancy or clever going on

[Lster]

I haven't:

* eaten
* drank
* gotten fully dress
* read the paper
* looked for job (do it every day)

Finishing the library will have to wait. I have priorities (and coding this showed where some of them are)

I guess you're in a different time zone to me.

[LaRoza]

I guess you're in a different time zone to me.

I got up later than normal, it is midday now.

[ruy_lopez]

Another objc implementation (I'm learning objc, if you hadn't guessed).

#import <objc/Object.h>

// Define the Fraction class
@interface Fraction : Object
{
	int numerator;
	int denominator;
}
- (Fraction *) initWith: (int) n: (int) d;
- (void) setNumerator: (int) n;
- (void) setDenominator: (int) d;
- (void) setTo: (int) n over: (int) d;
- (int)	numerator;
- (int)	denominator;
- (void) reduce;
- (double) convertToNum;
- (void) print;
- (void) printMixed;
@end

// Define the MathOps category
@interface Fraction (MathOps)
- (Fraction *) add: (Fraction *) f;
- (Fraction *) mul: (Fraction *) f;
- (Fraction *) sub: (Fraction *) f;
- (Fraction *) div: (Fraction *) f;
- (Fraction *) reciprocal: (Fraction *) f;
@end

#import "Fraction.h"
#import <stdio.h>
#include <math.h>
#include <stdlib.h>

@implementation Fraction;
-(Fraction *) initWith: (int) n: (int) d;
{
	self = [ super init ];

	if (self)
		[ self setTo: n over: d ];

	return self;
}

-(void) setNumerator: (int) n
{
	numerator = n;
}

-(void) setDenominator: (int) d
{
	denominator = d;
}

-(int) numerator 
{
	return numerator;
}

-(int) denominator
{
	return denominator;
}

-(double) convertToNum
{
	if (denominator != 0)
		return (double) numerator / denominator;
	else
		return 0.0;
}

-(void) setTo: (int) n over: (int) d
{
	numerator = n;
	denominator = d;
}

- (void) reduce
{
	int	u = numerator;
	int	v = denominator;
	int	temp;

	if (u < 0)
		u = -u;

	while (v != 0) {
		temp = u % v;
		u = v;
		v = temp;
	}

	numerator /= u;
	denominator /= u;
}	

-(void) print 
{
	printf (" %i/%i ", numerator, denominator);
}

- (void) printMixed
{
	Fraction *result = [[Fraction alloc] init];
	int whole_part;
	div_t tdiv;

 	if (numerator >= denominator) {
		if (numerator == denominator) {
			printf(" 1 ");
			return;
		}
		tdiv = div(numerator, denominator);
		whole_part = tdiv.quot;
		if (tdiv.rem != 0) {
			[result setTo: tdiv.rem over: denominator];
			[result reduce];
			printf(" %i+%i/%i ", whole_part, [result numerator], 
                                                                  [result denominator]);
			return;
		}
		else {
			printf(" %i ", whole_part);
			return;
		}
	}
	else
		[self print];
}
@end

/* MathOps category implementation */
@implementation Fraction (MathOps);
-(Fraction *) add: (Fraction *) f
{
	Fraction *result = [[Fraction alloc] init];
	int resultNum, resultDenom;

	resultNum = (numerator * [f denominator]) + 
		(denominator * [f numerator]);
	resultDenom = denominator * [f denominator];
	[result setTo: resultNum over: resultDenom];
	[result reduce];

	return result;
}

-(Fraction *) sub: (Fraction *) f
{
	Fraction *result = [[Fraction alloc] init];
	int resultNum, resultDenom;

	resultNum = (numerator * [f denominator]) - 
		(denominator * [f numerator]);
	resultDenom = denominator * [f denominator];
	[result setTo: resultNum over: resultDenom];
	[result reduce];

	return result;
}

- (Fraction *) mul: (Fraction *) f
{
	Fraction *result = [[Fraction alloc] init];

	[result setTo: numerator * [f numerator]
		 over: denominator * [f denominator]];
	[result reduce];

	return result;
}

- (Fraction *) div: (Fraction *) f
{
	Fraction *result = [[Fraction alloc] init];

	[result setTo: numerator * [f denominator]
		 over: denominator * [f numerator]];
	[result reduce];

	return result;
}

- (Fraction *) reciprocal: (Fraction *) f
{
	Fraction *result = [[Fraction alloc] init];

	[result setTo: denominator over: numerator];
	[result reduce];

	return result;
}
@end

#import "Fraction.h"

int main (int argc, char *argv[])
{
	Fraction  *a;
	Fraction  *b;
	Fraction  *result;
	
	a = [[Fraction alloc] init];
	b = [[Fraction alloc] init];

	[a setTo: 4 over: 3];
	[b setTo: 2 over: 8];

	[a print]; 
	printf (" + "); 
	[b print]; 
	printf (" = ");
	result = [a add: b];
	[result print];
	printf("\t = ");
	[result printMixed];
	printf("\t = %e\n", [result convertToNum]);

	[a print];
	printf(" - ");
	[b print];
	printf(" = ");
	result = [a sub: b];
	[result print];
	printf("\t = ");
	[result printMixed];
	printf("\t = %e\n", [result convertToNum]);

	[a print]; 
	printf (" * "); 
	[b print]; 
	printf (" = ");
	result = [a mul: b];
	[result print];
	printf("\t\t\t = %e\n", [result convertToNum]);

	[a print]; 
	printf(" / "); 
	[b print]; 
	printf(" = ");
	result = [a div: b];
	[result print];
	printf("\t = ");
	[result printMixed];
	printf("\t = %e\n", [result convertToNum]);

	[a free];
	[b free];
	[result free];

	return 0;
}

compile with -lobjc and -lm

EDIT: added printMixed to handle mixed fractions. I might add convert decimal to fraction later. (I'm getting whitespace inserted into my code blocks when I post)

[insineratehymn]

Like I said above, I had to write this program for a class anyway...
The teacher is kind of weird, he won't let us use anything that he hasn't taught us yet... so no classes or anything.


Das Code:

#include <iostream>
#include <string>
using namespace std;

// End pre-processor directives...

/*
  Program: Team Project
  Author: CHRIS TERRY
  Date written: 2/20/2008
  
  This of each fractal equation like this:
  (numeratorOne / denominatorOne) + (numeratorTwo / denominatorTwo)

  This is of course assuming that you want to add them.
  Assumptions/Checks: 
    Denominators are NOT 0
    Menu choices can only be 0 - 5
    The user only wants to do an equation regarding two(2) fractions
    There are NO command args
    Debug mode is choice 5 on the menu, it will restart the menu

  If you got this, please use it appropriately.
*/
    

bool DEBUG = false;

// Global debug variable...

void menu(int&);
void addFractions(int, int, int, int, int&, int&);
void subtractFractions(int, int, int, int, int&, int&);
void multiplyFractions(int, int, int, int, int&, int&);
void divideFractions(int, int, int, int, int&, int&);
void getNumbers(int&, int&, int&, int&, char);
int returnProduct(int, int);

// End method prototyping...

int main() {
  
  int finalNumerator, finalDenominator;
  // The finals...
  
  int numeratorOne, numeratorTwo, denominatorOne, denominatorTwo;
  // The numbers the will enter...

  int menuChoice = 0;
  // The menu item they enter...

  char symbol;
  // Which symbol for the equation...

  menu(menuChoice);
  // Get which method they want to do...

  switch(menuChoice) {
    // Determines which symbol based on which operation they want to perform...

  case 1: symbol = '+'; break;
  case 2: symbol = '-'; break;
  case 3: symbol = 'x'; break;
  case 4: symbol = '/'; break;
  }
  // End switch-case...

  getNumbers(numeratorOne, numeratorTwo, denominatorOne, denominatorTwo, symbol);
  // Get their numbers...

  if(DEBUG) cout << endl <<  numeratorOne << denominatorOne << numeratorTwo << denominatorTwo << endl;
  // Debug code...

  switch(menuChoice) {
    // Switch to determine witch method to call...

  case 1: {
    // The addition case...

    addFractions( numeratorOne, numeratorTwo, denominatorOne, denominatorTwo, finalNumerator, finalDenominator);
    // Call the method...

     break;
  } 
  case 2: {
    // The subtraction case...
    
    subtractFractions ( numeratorOne, numeratorTwo, denominatorOne, denominatorTwo, finalNumerator, finalDenominator );
    // Call the method...

    break;
  }
  case 3: {
    // The multiplication case...
    
    multiplyFractions ( numeratorOne, numeratorTwo, denominatorOne, denominatorTwo, finalNumerator, finalDenominator );
    // Call the method...

    break;
  }
  case 4: {
    // The division case...

    divideFractions ( numeratorOne, numeratorTwo, denominatorOne, denominatorTwo, finalNumerator, finalDenominator );
    //Call the method...

    break;
  }
   
  }
  // End switch-case...

  cout << endl << "Your problem was: ( " << numeratorOne << " / " << denominatorOne
       << " ) " << symbol << " ( " << numeratorTwo << " / " << denominatorTwo << " )" << endl;
  // Output their original problem...
  
  cout << "Your answer is: " << finalNumerator << " / " << finalDenominator << endl;
  // Output the answer...

  cout << "Just for fun, the decimal answer is: " << (finalNumerator + 0.0) / (finalDenominator + 0.0) << endl;
  // I like to make sure the numbers are real, so output the decimal value...

  cout << "Remember, this program does NOT calculate the lowest common denominator." << endl;
  // Disclaimer...

  return 0;
  // Terminate the program...
}

void divideFractions( int numeratorOne, int numeratorTwo, int denominatorOne,
		      int denominatorTwo, int& finalNumerator, int& finalDenominator ) {
  // The division method...

  if(DEBUG) cout << endl << "divideFractions: Entering method..." << endl;
  // Debug code...

  int newNumerator = returnProduct(numeratorOne, denominatorTwo);
  // Get the numerator: numeratorOne * denominatorTwo

  int newDenominator = returnProduct(denominatorOne, numeratorTwo);
  // Get the denominator: denominatorOne * numeratorTwo

  finalNumerator = newNumerator;
  finalDenominator = newDenominator;
  // Set the references one we have both the values...

  if(DEBUG) cout << endl << finalNumerator << finalDenominator << endl;
  //Debug code...
}

void multiplyFractions( int numeratorOne, int numeratorTwo, int denominatorOne,
			int denominatorTwo, int& finalNumerator, int& finalDenominator ) {
  // The multiplication method...

  if(DEBUG) cout << endl << "multiplyFractions: Entering method..." << endl;
  // Debug code...

  int newNumerator = returnProduct(numeratorOne, numeratorTwo);
  // Get the numerator: numeratorOne * numeratorTwo

  int newDenominator = returnProduct(denominatorOne, denominatorTwo);
  // Get the denominator: denominatorOne * denominatorTwo
  
  finalNumerator = newNumerator;
  finalDenominator = newDenominator;
  // Apply the references once we have the values...

  if(DEBUG) cout << endl << finalNumerator << finalDenominator << endl;
  // Debug code...
}

int returnProduct( int numberOne, int numberTwo ) {
  return numberOne * numberTwo;
  // All this method does is return the product of variable 1 by variable 2...
}

void subtractFractions ( int numeratorOne, int numeratorTwo, int denominatorOne, 
			 int denominatorTwo, int& finalNumerator, int& finalDenominator ) {
  // The subtraction method...

  if(DEBUG) cout << endl << "subtractFractions: Entering method... " << endl;
  // Debug code...

  int commonDenominator = returnProduct( denominatorOne, denominatorTwo );
  // Get the common denominator: denominatorOne * denominatorTwo

  int newNumeratorOne = returnProduct(numeratorOne, denominatorTwo);
  // Get the first numerator: numeratorOne * denominatorTwo

  int newNumeratorTwo = returnProduct(numeratorTwo, denominatorOne);
  // Get the second numerator: numeratorTwo * denominatorOne

  finalNumerator = newNumeratorOne - newNumeratorTwo;
  // The final numerator is the first minus the second...

  finalDenominator = commonDenominator;
  // Apply the references one we compute the values...

  if(DEBUG) cout << endl << commonDenominator << finalNumerator << finalDenominator << endl;
  // Debug code...
}

void addFractions ( int numeratorOne, int numeratorTwo, int denominatorOne, 
		    int denominatorTwo, int& finalNumerator, int& finalDenominator) {
  if(DEBUG) cout << endl << "addFractions: Entering method..." << endl;
  // Debug code...
  
  int commonDenominator = returnProduct(denominatorOne , denominatorTwo);
  // Calculate the common denominator...

  int newNumeratorOne = returnProduct(numeratorOne , denominatorTwo);
  // Calculate the first new numerator...

  int newNumeratorTwo = returnProduct(numeratorTwo , denominatorOne);
  // Calculate the second new numerator...

  finalNumerator = newNumeratorOne + newNumeratorTwo;
  // Calculate the final numerator...

  finalDenominator = commonDenominator;
  // Calculate the final denominator...

  if(DEBUG) cout << endl << commonDenominator << finalNumerator << finalDenominator << endl;
  // Debug code...
}

void getNumbers( int& numeratorOne, int& numeratorTwo, int& denominatorOne, int& denominatorTwo, char symbol) {
  // This method just gets the numbers from the user with a pretty menu...

  if(DEBUG) cout << endl << "getNumbers: Entering method..." << endl;
  // Debug code...

  do {
    cout << endl << "I am here to get your desired numerators and denominators" << endl;
    cout << "Please enter them in this fashion: 1 2 3 4" << endl;
    cout << "Please note the SPACES between the numbers." << endl;
    cout << "Thus, 1 2 3 4 would mean: ( 1 / 2 ) " << symbol << " ( 3 / 4 ) " << endl;
    cout << "I'll take those numbers now: ";
    // Output a nice little input prompt...

    cin >> numeratorOne >> denominatorOne >> numeratorTwo >> denominatorTwo;
    // Get the numbers...

    if((denominatorOne == 0) || (denominatorTwo == 0)) {
      cout << endl << "You cannot have a denominator equal to 0. Please try again." << endl;
    }
    // Check for division by 0...

  } while ( (denominatorOne == 0) || (denominatorTwo == 0));
    // Run while the denominators are equal to 0...
   
}

void menu(int& menuChoice) {
  // This is the menu method, it passes the choice back up to main...
  
  do {
    cout << "Welcome to the fraction calculator" << endl;
    cout << "Your choices are:" << endl;
    cout << "\t0) Replay Menu" << endl;
    cout << "\t1) Add Fractions" << endl;
    cout << "\t2) Subtract Fractions" << endl;
    cout << "\t3) Multiply Fractions" << endl;
    cout << "\t4) Divide Fractions" << endl;
    ( DEBUG ) ? cout << "\t5) DEBUG MODE OFF" << endl : cout << "\t5) DEBUG MODE ON" << endl;
    cout << "Please enter your choice( ex. 1 ): ";
    cin >> menuChoice;
    // Get the actual choice after advisal...
    if ( menuChoice == 5 ) {
      DEBUG = !DEBUG;
      menuChoice = 0;
    }
    if ( ( menuChoice < 0 ) || ( menuChoice > 5 ) ) {
      cout << "Please enter a number 0 - 4." << endl;
      menuChoice = 0;
    }
    // If it is 0 (or anything else), we will reprint the menu...

  } while( menuChoice == 0 );
  // End menu...

  if(DEBUG) cout << endl << "Menu: Exit do-while... " << menuChoice << endl;
  // Debug code...
}

Output:

Welcome to the fraction calculator
Your choices are:
        0) Replay Menu
        1) Add Fractions
        2) Subtract Fractions
        3) Multiply Fractions
        4) Divide Fractions
        5) DEBUG MODE ON
Please enter your choice( ex. 1 ): 5
Welcome to the fraction calculator
Your choices are:
        0) Replay Menu
        1) Add Fractions
        2) Subtract Fractions
        3) Multiply Fractions
        4) Divide Fractions
        5) DEBUG MODE OFF
Please enter your choice( ex. 1 ): 1

Menu: Exit do-while... 1

getNumbers: Entering method...

I am here to get your desired numerators and denominators
Please enter them in this fashion: 1 2 3 4
Please note the SPACES between the numbers.
Thus, 1 2 3 4 would mean: ( 1 / 2 ) + ( 3 / 4 ) 
I'll take those numbers now: 1 2 3 4

1234

addFractions: Entering method...

8108

Your problem was: ( 1 / 2 ) + ( 3 / 4 )
Your answer is: 10 / 8
Just for fun, the decimal answer is: 1.25
Remember, this program does NOT calculate the lowest common denominator.

[pedro_orange]

fraction.h

typedef struct
{
    int num;
    int denom;
} * Fraction;

Fraction addFraction(Fraction,Fraction);
Fraction getReciprocal(Fraction);
Fraction multiplyFraction(Fraction,Fraction);
Fraction newFraction(int,int);
Fraction subFraction(Fraction,Fraction);

void deleteFraction(Fraction);
int getCommonDenom(Fraction,Fraction);
void printFraction(Fraction,int); 

Very nice.
Forgot to declare:

Fraction divideFraction(Fraction,Fraction);

In the header. But otherwise, smashing stuff.