Simple calculator in C

 Hello, I've made simple calculator using C language and It can perform basic commands of calculator like Addition, Subtraction etc on 2 numbers.

Here is its code:-)

#include<stdio.h>

#include<stdlib.h>

int main()

{

    int num1,num2;

    char ch;

    float r,p;

    printf("This is calculator\n");

    printf("for sum type + sign\n");

    printf("for substracation type - sign\n");

    printf("for multipllication type * sign\n");

    printf("for devision type / sign\n");

    scanf("%c",&ch);

    printf("enter two numbers");

    scanf("%d%d",&num1,&num2);

    switch(ch)

        {

            case '+':

                printf("sum is %d",num1+num2);

                break;

            case '-':

                printf("sub. is %d",num1-num2);

                break;

            case '*':

                printf("multi. is %d",num1*num2);

                break;

            case '/':

                r = num1/num2;

                printf("devision is %f",r);

                break;

            default:

                printf("invalid input");

        }

    return 0;

}