c++ Calc Code

[treyriggins]

Hi If anyone could help me I would appreciate it. I am trying to make a calculator program. I am currently using MS Studios 2010, with Window 7 Premium system. This is where I am so far:

#include<math.h>
#include <iostream>

using namespace std;



int main()
{
int x,y,ans,i;
int choice;
float div;
char loop;
ans=0;

void clrsc();

do
{
printf("\n Do you wish to continue (Y/N) : ");
scanf_s("%s",&loop);

if (loop=='y' || loop=='Y')
{
clrsc();
printf("\n Enter any two numbers ");
printf("\n --------------------- ");

printf("\n\n Enter the first number : ");
scanf_s("%d",&x);

printf("\n Enter the second number : ");
scanf_s("%d",&y);

clrsc();
printf("\n Select the operation to be carried out ");
printf("\n -------------------------------------- ");

printf("\n 1. Addition ");
printf("\n 2. Substraction ");
printf("\n 3. Multiplication ");
printf("\n 4. Division ");

printf("\n Enter your choice : ");
scanf_s("%d",&choice);

switch(choice)
{
case 1 :
{
ans = x+y;
printf("\n Answer = %d",ans);
break;
}
case 2 :
{
ans = x-y;
printf("\n Answer = %d", ans);
break;
}
case 3 :
{
ans = x*y;
printf("\n Answer = %d", ans);
break;
}
case 4:
{
div = x/y;
printf("\n Answer = %.2f", div);
break;
}
default:
printf("\n\n Illegal operation......");
break;
}
}
else
printf("\n Bye....... Bye...........");
cin.get();
}while(loop=='y' || loop=='Y');
}

[Beniamin Kalinowski]

Could you paste it as a code? in square brackets code?

[Nexius]

Another way to do it is with callback functions.
It's fairly simple, so I'm not going to use any class this time.

#include <iostream>
#include <map>
#include <math.h>
#include <string>

typedef float (*callback)(float, float);
/*natives begin*/
float add(float f, float s)
{
	return f+s;
}
float sub(float f, float s)
{
	return f-s;
}
float div(float f, float s)
{
	if(s)
		return f/s;
	std::cout << "Cannot divide by zero" << std::endl;
	return 0.0f;
}
float mult(float f, float s)
{
	return f * s;
}
float power(float f, float s)
{
	return pow(f, s);
}
/*natives end*/

void prompt(bool &b)
{
	std::cout << "continue? y : n" << std::endl;
	char c;
	std::cin >> c;

	if(c == 'n' || c == 'N')
		b= true;
}

int main()
{
	std::map<std::string, callback> functions;
	functions["+"] = add;
	functions["-"] = sub;
	functions["/"] = div;
	functions["*"] = mult;
	functions["^"] = power;
	for(bool isFinished= false; !isFinished; prompt(isFinished))
	{
		std::cout << "Enter an expression\n[number] [operation] [number]" << std::endl;
		float f, s;
		std::string op;
		std::cin >> f >> op >> s;
		
		if(functions.find(op) != functions.end())
			std::cout << "The result is: " << functions[op](f,s) << std::endl;
		else
			std::cout << "operation not found" << std::endl;
	}
}

[treyriggins]

Thanks, I'll try that.

[Latrakx]

It is kind of a bad calculator, but I think it might be a little more efficient thinking about number of lines:

#include <iostream>

int main ()
{
	using namespace std;

	float num1;
	float num2;

	cout << "Write your first number(use punctuary for desimals, not comma) :\n";
	

	cin >> num1;
	cout << "Now write your second number :\n";
	cin >> num2;

	float numm = num1*num2;
	float nump = num1+num2;
	float nummi = num1-num2;
	float nums = num1/num2;
	
	cout << "\n" << num1 << "*" << num2 << "=";
	cout << numm << "\n \n" ;
	cout << num1 << "+" << num2 << "=";
	cout << nump << "\n \n" ;
	cout << num1 << "-" << num2 << "=";
	cout << nums << "\n \n" ;
	cout << num1 << "/" << num2 << "=";
	cout << nums << "\n \n";
	
	cin.get();
	cin.get();
}

Edit: Also, in the future post your source-code in "Source Code" format.