HOW TO MAKE a FOUR FUNCTIONAL CALCULATOR IN CPP

Calculators are used to everyone in daily life. A simple calculator can be made using a C++ program which is able to add, subtract, multiply and divide, two operands entered by the user. The if and goto statement is used to create a calculator.

you can use any type of IDE

eg geny ,cfree ,visual studio etc ....

#include<iostream>
using namespace std;
int main()
{
	char a;
	float z;
	goto r;

	r :
	{
		system("cls");
	cout<<"enter '+' for addition" << endl << "enter '-' for subtraction" << endl << "enter '*' for multiplication " << endl << "enter  '/' for division "<<endl;
    cin>> a;
	if (a=='+')
    {
    	float x,y;
    	cout<<"enter first number"<<endl;
    	cin >>x;
    	cout<<"enter second  number"<<endl;
    	cin >>y;
    	z=x+y;
    	cout<<"sum of "<<x<<"+"<<y<<"="<<z<<endl;
   	}
   	 else if (a=='-')
    {
    	float x,y;
    	cout<<"enter first number"<<endl;
    	cin >>x;
    	cout<<"enter second  number"<<endl;
    	cin >>y;
    	z=x-y;
    	cout<<"subtraction of "<<x<<"-"<<y<<"="<<z<<endl;
   	}
   	else if (a=='*')
    {
    	float x,y;
    	cout<<"enter first number"<<endl;
    	cin >>x;
    	cout<<"enter second  number"<<endl;
    	cin >>y;
    	z=x*y;
    	cout<<"multiplicative product of "<<x<<"*"<<y<<"="<<z<<endl;
   	}
   	else if (a=='/')
    {
    	float x,y;
    	float z;
    	cout<<"enter first number"<<endl;
    	cin >>x;
    	cout<<"enter second  number"<<endl;
    	cin >>y;
    	z=x/y;
    	cout<<"division of "<<x<<"/"<<y<<"="<<z<<endl;
   	}
   	else
   	   {
	   	cout << "unknown operation \n"; 
	   }
	   goto p;
	}
	p :
   	cout<< "to continue enter 'r' "<<endl<<"to close enter 'c'";
   cin>>a;
   if (a=='r')
   {
   	goto r;
   }
   else if(a=='c')
   {
   	goto e;
   }
   else 
   {
   	goto p;
   }
 e :{
 	
 }
}