Make Calculator in C Language .Get source code Free

/*********************************************
PROGRAM NAME- CALCULATOR
PROGRAMMER - RAJNISH KUMAR,
Editor- Turbo C++


In Thish program,i created a simpal calculator,
 (Useing Switch() function.)
**********************************************/
//import header File
#include<stdio.h>

void main()     //start of main() function
{
 int n,num1,num2,result;    //Define variable
 char option;
 clrscr();
  /* Here, the whole program run in do-while Loop,bacause if User want
   to contionu this program,they can do.*/

  do{
  printf("\n What opration do you want to do?\n");
  printf("press 1 for addition\n");
  printf("press 2 for subtraction\n");
  printf("press 3 for multiplication\n");
  printf("press 4 for division\n");
  scanf("%d",&n);

  printf("please enter a 1st number\n"); //asking for 1st Number
  scanf("%d",&num1);
  printf("please enter a 2nd number\n");// 2nd Number
  scanf("%d",&num2);

 //start of switch case function//
  switch(n)
  {
   case 1:result=num1+num2;
printf("addition of two number is %d",result);
break;
    case 2:result=num1-num2;
printf("subtraction of two number is %d",result);
break;
    case 3:result=num1*num2;
printf("multiplication of two number is %d",result);
break;
    case 4:result=num1/num2;
printf("division of two number is %d",result);
break;
  default:printf("wrong input");
 }
  //End of switch function//

  printf("\n do you want to continue y/n?\n"); //ask for continue or Not.
  option=getche();
  }
  while(option=='y');

  getch();

}