using System.Collections.Generic;
public static void Main()
Console.WriteLine("Hello World");
var list = new List<temp>();
list.Add(new temp{name = "a", age = 1});
list.Add(new temp{name = "b", age = 2});
int[] ageArray = new[] {1,12,13};
var result = list.Where(x => ageArray.Contains(x.age)).ToList();
Console.WriteLine(result.Count);