Calculator

#include <cs50.h>
#include <stdio.h>
#include <stdlib.h>
int main(int argc, string argv[])
{
    if (argc != 4) //make sure the user inputs 4 arguments
    {
        printf("Please enter two numbers and an operation (./calc 4 + 4)\n");
        return 1;
    }
    float num1 = atof(argv[1]); //get the first number
    float num2 = atof(argv[3]); //get the second
    char op = argv[2][0]; //get the operator
    float output;
    if (op == '+') //if addition
    {
        output = num1 + num2;
    }
    else if (op == '-') //if subtraction
    {
        output = num1 - num2;
    }
    else if (op == 'x') //if multiplication
    {
        output = num1 * num2;
    }
    else if (op == '/') //if division
    {
        output = num1 / num2;
    }
    else if (op == '%') //if module
    {
        output = ((float)(( (int)(num1 * 1000)) % ( (int)(num2 * 1000)))) / 1000;
        /*multiple each number by 1000 and convert to int, then preform module operation
        convert to a float, then divide by 1000
        */
    }
    else
    {
        printf("enter a valid operator (+,-,x,/,%%");
        return 1;
    }
    printf("%.6f\n", output);
    return 0;
}



/*desired output exampel
~/workspace/chapter2/ $ ./calc 4 + 5
9.000000
or, indeed like this (allowing the user to perform some basic floating-point arithmetic)

~/workspace/chapter2/ $ ./calc 8.38 - 5.12
3.260000
*/