using System;
using System.Linq;
using System.Collections.Generic;
public class Program
{
public static void Main()
int fib = Enumerable.Range(1, 10).Skip(2).Aggregate(new KeyValuePair<int, int>(1, 1), (seq, index) => new KeyValuePair<int, int>(seq.Value, seq.Key + seq.Value)).Value;
Console.WriteLine(fib);
}