Thread: Simple Calculator

this is a calculator which adds, subtracts, divides, multiplies, calculates areas and perimeters of a circle. although all appears fine to me, whenever i choose to add subtract or whatever, this is what happens. Example:

input:
2 + 3

output:
1972340 + 2348912 = blah blah...

aditionally, the management of pi number doesn't seem to work. It all stops when you click option 5 and 6, while it is supposed to ask you for a value to pi or to use the default one.

Code:

/*
//  SimpleCal
//
//  Created by Mario Nascimento on 2/26/12.
//  <dimCode>
*/


#include <stdio.h>
#include "linech.h"
#include <stdlib.h>
double pi=3.1415926535897932384626433832795028841971693993751058209749445923078164062862089986280348253421170679821480865132823066470938446095505822317253594081284811174502841027019385211055596446229489549303819644288109756659334461284756482337867831652712019091456485669234603486104543266482133936072602491412737245870066063155881748815209209628292540917153643678925903600113305305488204665213841469519415116094330572703657595919530921861173819326117931051185480744623799627495673518857527248912279381830119491;


int sum();
int subtract();
int mult();
int divi();
int circa();
int circac();
int circp();
int circpc();
void exitt(void);
int main()
{
	putchar('\n');
	line(25,'*');
	puts("\nWELCOME TO MARIOTUTORIALS\n");
	line(25,'*');
	int i = 0;
	do
	{
		printf("\n\t[1.] \tSum");
		printf("\n\t[2.] \tSubtraction");
		printf("\n\t[3.] \tMultiplication");
		printf("\n\t[4.] \tDivision");
		printf("\n\t[5.] \tArea od Circle");
		printf("\n\t[6.] \tPerimeter of Circle");
		printf("\n\t[7.] \tEXIT");
		printf("\nChoose a number:\n $ ");
		scanf(" %d", &i);
		fflush(stdin);
		switch(i)
		{
			case 1 : sum(); break;
			case 2 : subtract(); break;
			case 3 : divi(); break;
			case 4 : mult(); break;
			case 5 : circa(); break;;
			case 6 : circp(); break;
			case 7 : exitt();
		}
		getchar();
	}
	while(i != 3);
	getchar();
}
int sum()
{
    
	double n1 = 0.0;
	double n2 = 0.0;
	printf("Insert two numbers (separated by + sign): ");
	scanf("%d + %d", &n1, &n2);
	
	printf("%d + %d = %d", n1, n2, (n1+n2));
	getchar();
    printf("\nPress Enter to Return to Main Menu");
    getchar();
	main(system("clear"));
    
}
int subtract()
{
    
	double n1 = 0.0;
	double n2 = 0.0;
	printf("Insert two numbers (separated by - sign): ");
	scanf("%d - %d", &n1, &n2);
	
	printf("%d - %d = %d", n1, n2, (n1-n2));
	getchar();
    printf("\nPress Enter to Return to Main Menu");
    getchar();
	main(system("clear"));
}


int mult()
{
	double n1 = 0.0;
	double n2 = 0.0;
	printf("Insert two numbers (separated by * sign): ");
	scanf("%d * %d", &n1, &n2);
	
	printf("%d * %d = %d", n1, n2, (n1*n2));
	getchar();
    printf("\nPress Enter to Return to Main Menu");
    getchar();
	main(system("clear"));
}


int divi()
{
	double n1 = 0.0;
	double n2 = 0.0;
	printf("Insert two numbers (separated by / sign): ");
	scanf("%d / %d", &n1, &n2);
	
	printf("%d / %d = %d", n1, n2, (n1/n2));
	getchar();
    printf("\nPress Enter to Return to Main Menu");
    getchar();
	main(system("clear"));
}


int circa()
{
	double j = 0.0;
	printf("Enter a value for pi (enter 1 for default 500-digit) $ ");
	scanf("%d",&j);
	if(j==1)
	{
		circac();
	}
	else
		pi == j;
		circac();
}
circac()
{
	double n1 = 0.0;
	printf("Insert radius of circle: ");
	scanf("%d", &n1);
	printf("Area of Circle = %d",(pi * n1 * n1) );
	getchar();
    printf("\nPress Enter to Return to Main Menu");
    getchar();
	main(system("clear"));
}


int circp()
{
	double k = 0.0;
	printf("Enter a value for pi (enter 1 for default 500-digit) $ ");
	scanf("ß%d",&k);
	if(k==1)
	{
		circpc();
	}
	else
		pi == k;
		circpc();
}


circpc()
{
	double n1 = 0.0;
	printf("Insert radius of circle: ");
	scanf("%d", &n1);
	printf("Perimeter of Circle = %d",(pi * n1 * 2));
	getchar();
    printf("\nPress Enter to Return to Main Menu");
    getchar();
	main(system("clear"));
}


void exitt(void)
{
	printf("\nPress [Enter] to exit");
}

Sorry here it is!

I have now put the code. I initialized them. As they are doubles I initializes as: double n1 = 0.0;

oh my god how stupid.... Thank you. I've corrected and used %f but now when I input, say 5 + 1 the result is: 0.0000 + 0.0000 = 0.0000

The scanf() format specifier for double is not "%f" it is "%lf" that is a lower case L not a 1.

Jim

Thank you, I had no idea actually I thought it was the same as float. It works now. Everything except the area and perimeter of circle. I can't seem to find any error in the code. And by the way, is there anyway like in pascal to limit the amount of decimal points it prints out? Thank you.

I'm on a mac (: the library works fine for macs just need to change cls to clear. I did that so that when it returns to main it clears the screen. thanks about the 500-digit (: what do you suggest instead of main(system("clear")); ?

that looks simpler, thank you. How about I make a void function lets call it clsret() the has both those command in it and then I just call it every time I need a return for my function.

Originally Posted by oogabooga

That won't work because the return will just return from THAT function. You'd still need a return in the original function.

But you could put this code that's repeated in each of your functions after your switch statement in main

Code:

    getchar();
    printf("\nPress Enter to Return to Main Menu");
    getchar();
    system("clear");

And note that your while condition in main should be i != 7 (not 3).

I still have a problem though. two actually. This one is solved but the other problem is that when you choose option 5 or 6 it will ask you for a value of pi. Now the end result is correct but whether you enter 10.2 as pi or 1.05 the result is the same. It is using the first value attributed to pi in the beginning. The last problem is that I wanted to sometimes make the printf() function only print numbers for example with 2 decimal points instead of 5