crappycalc.c

/* Calculator Assignment 5
 *
 * A simple calculator program controlled program, controlled by a menu and
 *   divided into separate functions.
 *
 * Name: Brandon Jank
 * Section: CS 120-05
 * Due Date: 10/06/2014
 * Assignment #5
 *
 * v1.0.0 - 2014/09/30 - Assignment 5 - Copied program from book.
 * - Fixed the way the program exits so that it doesn't reprint the user's last answer.
 * - Added subtraction and multiplication options.
 * - Added a minimum option to the program. It should accept two numbers and return the smaller one.
 * - Added an option that returns a random number between 0 and an upper bound given by the user.
 * - Added and option to calculate the volume of a cylinder.
 */

#include <iostream>
#include <time.h> // time()
#include <math.h> // M_PI
#include <cmath> // pow()
#include <cstdlib> // rand(), srand()
#include "CurseWin.h"
using namespace std;

//---------- Function Prototypes -----------
void print_menu(CurseWin &);
double get_value(CurseWin &);
double divide(double, double);
double subtraction(double, double); // Assignment 5
double multiplication(double, double); // Assignment 5
double minimum(double, double); // Assignment 5
double random(int); // Assignment 5
double volume_cylinder(double, double); // Assignment 5

//--------------  Main -------------------
int main()
{
    CursWin outputWin(0,0,2,79), inputWin(2,0,6,50), menuWin(2,50,6,79);
    
    double operand1, operand2, answer;
    int choice, valid_choice;
    char Operator;
    print_menu(menuWin);
        
    do{
        srand(time(NULL)); // Assignment 5: Make random more random
        inputWin << "Enter a menu choice: " << cflush;
        inputWin >> choice;
        valid_choice = 1;           // assume choice is valid
        switch(choice){
            case 0:                    // program will exit
                break;
            case 1:                    // addition
                operand1 = get_value(inputWin, "first value");
                operand2 = get_value(inputWin, "second value");
                answer = operand1 + operand2;
                Operator = '+';
                break;
            case 2:                    // division
                operand1 = get_value(inputWin, "first value");
                operand2 = get_value(inputWin, "second value");
                answer = divide(operand1,operand2);
                Operator = '/';
                break;
            case 3:                    // Assignment 5: subtraction
                operand1 = get_value(inputWin, "first value");
                operand2 = get_value(inputWin, "second value");
                answer = subtraction(operand1,operand2);
                Operator = '-';
                break;
            case 4:                    // Assignment 5: multiplication
                operand1 = get_value(inputWin, "first value");
                operand2 = get_value(inputWin, "second value");
                answer = multiplication(operand1,operand2);
                Operator = '*';
                break;
            case 5:                    // Assignment 5: minimum of two values
                operand1 = get_value(inputWin, "first value");
                operand2 = get_value(inputWin, "second value");
                answer = minimum(operand1,operand2);
                Operator = 'm';
                break;
            case 6:                    // Assignment 5: random with bound
                operand1 = get_value("integer for upper bound");
                answer = random(operand1);
                Operator = 'r';
                break;
            case 7:                    // Assignment 5: volume of a cylinder
                operand1 = get_value("radius");
                operand2 = get_value("height");
                answer = volume_cylinder(operand1,operand2);
                Operator = 'V';
                break;
            default:
                valid_choice = 0;   // choice is invalid
                inputWin << "Invalid Choice." << cendl;
            }
        if(valid_choice && choice != 0){   // if choice is valid, print the answer // Assignment 5: Do not reprint answer on exit.
            outputWin << cnl << operand1 << " " << Operator << " " << operand2 << " = " << answer << cendl;
        }
    }while(choice != 0);    // if not 0, loop back to start
    return 0;
}

//--------------  Functions -------------------
double divide(double dividend, double divisor){
    if(divisor == 0){
        return 0;  // avoids divide by zero errors
    }
    else
        return (dividend/divisor);
}

// Subtraction function for Assignment 5
double subtraction(double x, double y){ 
    return x - y;
}

// Multiplication function for Assignment 5
double multiplication(double x, double y){ 
    return x * y;
}

// Minimum of two values function for Assignment 5
double minimum(double x, double y){ 
    if (x < y) return x; else return y;
}

// Random number with upper bound function for Assignment 5
double random(int x){ 
    return rand() % x;
}

// Volume of a Cylinder function for Assignment 5
double volume_cylinder(double r, double h){ 
    return M_PI * pow(r,2) * h;
}

//----------------- get_value function ----------------
double get_value(CurseWin &inw, string value_name){
    double value;
    inw << "Please, enter the " << value_name << ": " << cflush;
    inw >> value;
    inw << cendl;
    return value;
}

//-------------------- print_menu function -------------
void print_menu(CurseWin &outw){
    outw << cnl;
    outw << "Add (1)" << cnl;
    outw << "Divide (2)" << cnl;
    outw << "Subtract (3)" << cnl;
    outw << "Multiply (4)" << cnl;
    outw << "Minimum (5)" << cnl;
    outw << "Random (6)" << cnl;
    outw << "Volume of a Cylinder (7)" << cnl;
    outw << "Exit (0)" << cnl;
    outw << "Enter your choice (0-7): " << cflush;
}