Thread: My first program without consulting with the book in my avatar!

It's just a basic fraction program (it adds, subtracts, multiplies and divides fractions). It might not seem like much maybe not to you guys. I think it signifies that I'm proficient in basic C++ programming (without pointers and stuff). Anyway, here's the program:

Code:

//Fraction Math by homeyg

#include <iostream>

using namespace std;

//function prototypes
void displayAdd(int num1, int num2, int den1, int den2);
void displaySub(int num1, int num2, int den1, int den2);
void displayMul(int num1, int num2, int den1, int den2);
void displayDiv(int num1, int num2, int den1, int den2);
int denomChange(int run1, int run2);
int denomChangeMul(int run1, int run2);
int denomChangeDiv(int rise, int run);
int numChangeAdd(int rise1, int rise2, int run1, int run2);
int numChangeSub(int rise1, int rise2, int run1, int run2);
int numChangeMul(int rise1, int rise2);
int numChangeDiv(int rise, int run);

int main()
{
    //array variable declarations (array is used to perform a check to see if one of the four operators was input
    int arrayCount = 4;
    char opArray[4];
    opArray[0] = '*';
    opArray[1] = '/';
    opArray[2] = '+';
    opArray[3] = '-';
    bool check;
    
    //variable declarations for the numerators and denominators, operation input, and for the loop control
    int cont;
    int num1;
    int denom1;
    int num2;
    int denom2;
    char operation;
    
    cout << "This program performs the four main mathematical operations on fractions, nothing fancy."<<endl
         << "This program will not display mixed numbers, only improper fractions."<<endl
         << "It will also not simplify the answers."<<endl;
    
    //main loop
    while(cont!=0)
    {
        //operation input
        cout << "What operation do you want to do (*,/,+,-)? ";
        cin  >> operation;
        //test to see if one of the four valid operators is used
        //if it is not, the main loop starts over
        for(int ind = 0;ind<arrayCount; ind++)
        {
            if(operation == opArray[ind])
            {
                check = true;
                break;   
            }
            if(operation != opArray[ind])
            {
                check = false;
            }    
        }
        if(check == false)
        {
            cout<<"Invalid operator."<<endl;
            continue;
        }        
        //numerator and denominator input section      
        cout << "Enter the numerator and denominator of the first fraction to be performed on."<<endl;
        cout << "Numerator: ";
        cin  >> num1;
        cout << "Denominator: ";
        cin  >> denom1;
        cout << num1 <<"/"<<denom1;
        cout << "\nEnter the numerator and denominator of the second fraction to be performed on."<<endl;
        cout << "Numerator: ";
        cin  >> num2;
        cout << "Denominator: ";
        cin  >> denom2;
        cout << num2 <<"/"<<denom2;
        //the function corresponding to the operator is called
        switch(operation)
        {
            case '+' : displayAdd(num1, num2, denom1, denom2);
            break;
            case '-' : displaySub(num1, num2, denom1, denom2);
            break;
            case '*' : displayMul(num1, num2, denom1, denom2);
            break;
            case '/' : displayDiv(num1, num2, denom1, denom2);
            break;
        }        

        //test if you want to continue
        cout << "Press any number to continue and 0 to quit. ";
        cin  >> cont;
    }    
    
    
    return 0;
}
//display functions
/////////////////////////////////////////////

void displayAdd(int num1, int num2, int den1, int den2)
{
    cout << "\nThe answer is: "
         << numChangeAdd(num1, num2, den1, den2) <<"/"<<denomChange(den1, den2)<<endl;
}

void displaySub(int num1, int num2, int den1, int den2)
{
    cout << "\nThe answer is: "
         << numChangeSub(num1, num2, den1, den2) <<"/"<<denomChange(den1, den2)<<endl;
}

void displayMul(int num1, int num2, int den1, int den2)
{
    cout << "\nThe answer is: "
         << numChangeMul(num1, num2) <<"/"<<denomChangeMul(den1, den2)<<endl;
}

void displayDiv(int num1, int num2, int den1, int den2)
{
    cout << "\nThe answer is: "
         << numChangeDiv(num1, den2) <<"/"<<denomChangeDiv(num2, den1)<<endl;
}                       
    
//denominator calculation functions
/////////////////////////////////////////////

int denomChange(int run1, int run2)
{
    if(run1!=run2)
    return run1 * run2;
    if(run1==run2)
    return run1;
}

int denomChangeMul(int run1, int run2)
{
    return run1 * run2;
}

int denomChangeDiv(int rise, int run)
{
    return rise * run;
}        

//numerator calculation functions
/////////////////////////////////////////////

int numChangeAdd(int rise1, int rise2, int run1, int run2)
{
    if(run1!=run2)
    {
        int firstNum = rise1 * run2;
        int secondNum = rise2 * run1;
        return firstNum + secondNum;
    }
    if(run1==run2)
    return rise1 + rise2;    
}

int numChangeSub(int rise1, int rise2, int run1, int run2)
{
    if(run1!=run2)
    {
        int firstNum = rise1 * run2;
        int secondNum = rise2 * run1;
        return firstNum - secondNum;
    }
    if(run1==run2)
    return rise1 - rise2;
}

int numChangeMul(int rise1, int rise2)
{
    return rise1 * rise2;
}

int numChangeDiv(int rise, int run)
{
    return rise * run;
}

Do any of you remember the first program you wrote unnassisted? I did write a smaller program before, but it had many problems before it finally worked. I think I had to resolve to the forums to solve it!

I don't know if I could figure out how to simplify the fractions or put them as mixed numbers without using another page of code so I just said forget it and went with unsimplified, improper fractions.

I have another idea for a program, however, it requires finding the square root of a number which I also don't know how to do. Is there a special function or operator for it?

sqrt()

All of my first programs were unassisted. It hasn't been until as of late that I've been buying books left and right.

First program I wrote I believe was a password protection system for comp at school. You had to login to the system or it would reboot the computer. I had the BIOS password protected as well.

Most embarassing thing that happened was that since I had locked out F5 and F8 in the Windows boot process by using the /SWITCHES option when my program failed due to a NULL pointer I had to remove the case cover, remove the BIOS jumper, and reset the whole thing.

Those were the days.

Whoah, I didn't know it was that simple...

I have bought 2 books in the last month...