using System;

using System.Linq;

using System.Collections.Generic;                   

​

public class Program

{

    public static void Main()

    {

        var num = GetNum(new int[]{-2, 2, 3, -4, 7, 1});

        Console.WriteLine(num);

    }

    public static int GetNum(int[] ts)

    {

        if(!ts.Any()) 

            return 0;

        int result = int.MaxValue;

        foreach(var num in ts)

        {

            if(Math.Abs(num) < result || result == -num)

                result = num;

        }

        return result;

    }

}