/*
 * Aresh Saharkhiz
 * saharkiz@gmail.com
 * Associate Professor / Mapua Institute of Technology / Philippines
 */

using System;

// Introduction to Software Testing
// Authors: Paul Ammann & Jeff Offutt
// Chapter 5, section 5.2, page 189

internal class sum_class
{

    //Effects: If x null throw NullPointerException
    //   else return the sum of the values in x
    public static int sum(int[] x)
    {
        int s = 0;
        for (int i = 0; i < x.Length; i++)
        {
            s = s + x[i];
            // s = s - x[i];
        }
        return s;
    }

    public static void Main(string[] argv)
    { // Driver method for sum
        // Read an array from standard input, call sum()
        int[] inArr = new int[argv.Length];
        if (argv.Length == 0)
        {
            Console.WriteLine("Usage: java numZero v1 [v2] [v3] ... ");
            return;
        }

        for (int i = 0; i < argv.Length; i++)
        {
            try
            {
                inArr[i] = Convert.ToInt32(argv[i]);
            }
            catch (FormatException)
            {
                Console.WriteLine("Entry must be a integer, using 1.");
                inArr[i] = 1;
            }
        }

        Console.WriteLine("The sum is: " + sum(inArr));
    }

}