Remove element from specific index of a list

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text.RegularExpressions;

namespace HelloWorld
{
public class Program
{
public static void Main(string[] args)
{
List<int> ls = new List<int>();
string str;
int num;
int num1;
ls.Add(11);
ls.Add(12);
ls.Add(13);
ls.Add(14);
ls.Add(15);
ls.Add(16);
foreach(int a in ls)
{
Console.WriteLine("List Number {0}",a);
}
Console.WriteLine("Which Element you want to delete");
str=Console.ReadLine();
int.TryParse(str, out num);
Console.WriteLine(num);
ls.RemoveAt(num);
Console.WriteLine("after deleting list");
foreach(int a in ls)
{
Console.WriteLine("List Number {0}",a);
}

	}
}

}