Project Euler 3
using System; using System.Collections.Generic; namespace PE { public class PE003 { public static void Calc() { long n = 600851475143; List<long> factors = new List<long>(); long x = 3; while (x*x <= n) { if (n % x == 0) { factors.Add(x); n /= x; } else { x += 2; } } if (n > 1) factors.Add(n); Console.WriteLine(factors[factors.Count-1]); } } }