// This program demonstrates the use of the atoi() function, located in
// <stdlib.h> standard library. This function converts an ascii code to an int
// This allows you to take a number from the command line (remember that this 
// will be as an ascii code, since you store command line arguments as strings!) 
// and convert that ascii code to an actual number that you can perform
// mathematical operations on. 

// Sasha Vassar Week 5, Lecture 10  

// ./atoi 8 9 10 

#include <stdio.h>

// The function atoi() is located in the standard library <stdlib.h>
#include <stdlib.h>

int main (int argc, char *argv[]) {
    
    //Remember that the command line arguments are strings, so if you need 
    //to do mathematical operations, you will need to convert them to numbers
    //You can do this with the help of the atoi() function in <stdlib.c>
    
    //Let's now print out all the command line arguments given and 
    //add them together to give the sum of command line arguments 
    
    int sum = 0;
    //Start the index at 1, because 0 is the program name
    int i = 1;
    while (i < argc) {
        printf("The command line argument at index %d (argv[%d]) is %d\n",
        i, i, atoi(argv[i]));
        sum = sum + atoi(argv[i]);
        i++;
    }
    printf("The sum of the command line arguments is %d\n", sum);
    return 0;
}