C - Calculator

#include <stdio.h>

float add(float num1, float num2);
float sub(float num1, float num2);
float mult(float num1, float num2);
float div(float num1, float num2);

int main(){

char op;
float num1, num2, result = 0.0f;

printf("Enter number, operator and number: ");
scanf("%f %c %f", &num1, &op, &num2);

switch(op){
case '+':
    result = add(num1, num2);
    break;
case '-':
    result = sub(num1, num2);
    break;
case '*':
    result = num1 * num2;
    break;
case '/':
    result = num1 / num2;
default:
    printf("Enter a valid operator");
}

printf("%.2f %c %.2f = %.2f", num1, op, num2, result);
return 0;
}

float add(float num1, float num2){
    return num1 + num2;
}

float sub(float num1, float num2){
    return num1 - num2;
}

float mult(float num1, float num2){
    return num1 * num2;
}

float div(float num1, float num2){
    return num1 / num2;
}