SimpleCalculatorUsingFunctions.c

#include <stdio.h>
int add(int a, int b);
int subtract( int a, int b);
int multiply( int a, int b);
float divide( int a, int b);
int main() {
   int num1, num2, result;
   int choice;
   printf("enter first number");
   scanf("%d", &num1);
   printf("enter second number");
   scanf("%d", &num2 );
   printf("enter choice, add{1}, subtract{2}, multiply{3}, divide{4} ");
   scanf("%d", &choice);
   switch(choice) {
       case 1:
       result = add(num1, num2);
       printf("%d+%d=%d", num1, num2, result);
       break;
       case 2:
       result = subtract(num1, num2);
       printf("%d-%d=%d", num1, num2, result);
        break;
       case 3:
       result = multiply(num1, num2);
       printf("%d*%d=%d", num1, num2, result);
        break;
       case 4:
       result = divide(num1, num2);
       printf("%d/%d=%d", num1, num2, result);
        break;
        default:
        printf("invalid choice");
   }
    return 0;
}
int add(int a, int b) {
    return a+b;
}
int subtract( int a, int b){
    return a-b;
}
int multiply( int a, int b) {
    return a*b;
}
float divide( int a, int b){
    return a/b;
}