using System;
using System.Linq;
using System.Collections.Generic;
class Ideone
{
static List<int> l = new List<int> {1,2,3};
static IEnumerable<int> Get() { return l; }
public static void Main(string[] args)
{
var list = Get() as List<int>;
list.Add(4);
Console.WriteLine(l.Count());
}
}
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