using System;
using System.Linq;
public class Program
{
public static void Main()
var strings = new string[] { "12", "abc", "1b", "0" };
var ints = strings.Select(s => Int32.TryParse(s, out var i) ? (int?)i : null).Where(i => i != null).Select(i => (int)i);
foreach (var i in ints)
Console.WriteLine(i * 100);
}