# C++ Program to Make a Simple Mathematical calculator

In this lesson we will learn C++ Program to Make a Simple Mathematical calculator by using switch statement. First we define switch structure and see syntax of switch structure of c/c++ language. Definition and syntax of switch structure are as follows
You can copy and make a source file compiler
To understand the example you must have the knowledge about Syntax of case statement and basic structure of c++.
This program takes an arithmetic operator (+, -, *, /) and two operands from user and performs the operation on those two operands depending upon the operator.

``````# include <iostream.h>
#include <conio.h>
void main()
{
char op;
float n1, n2;
cout << "Enter operator  + or - or * or /: ";
cin >> op;
cout << "Enter two operands: ";
cin >> n1 >> n2;
switch(op)
{
case '+':
cout << n1+n2;
break;
case '-':
cout << n1-n2;
break;
case '*':
cout << n1*2;
break;
case '/':
cout << n1/n2;
break;
case '/':
cout << n1%n2;
break;
default:
cout << "wrong oprater plz inter +,-,*,/ or %";
break;
}
getch();
}``````

## C program for simple calculator

C++ and c have almost same structure but only some differences

1. In c++ prepossess directive iostream.h is used for including stranded input output functions  while in c language stdio.h is used
2. For output cout is used in c++ while in c language printf  is used for output
3. In C++ cin is used for getting input from the user while in c coding scanf function is used for getting input from the user.
4. In c++ format specifier are not used to print output and for getting input while format specifier are used in c coding.
``````# include <stdio.h>
#include <conio.h>
void main()
{
clrscr();
char op;
float n1, n2;
printf( "Enter operator  + or - or * or /: ");
scanf("%c",op);
printf( "Enter two operands: ");
scanf("%f %f",&n1,&n2);
switch(op)
{
case '+':
printf("%f", n1+n2);
break;
case '-':
printf("%f", n1-n2);
break;
case '*':
printf("%f", n1*n2);
break;
case '/':
printf("%f", n1/n2);
break;
case '%':
printf("%f", n1%n2);
break;
default:
printf("wrong oprater plz inter +,-,*,/ or %");
break;
}
getch();
}``````