using System; using System.Linq; using System.Collections.Generic; using System.Text.RegularExpressions; class Program { static void Main() { var abc = Console.ReadLine().Split().Select(int.Parse).ToList(); var a = abc[0]; var b = abc[1]; var c = abc[2]; if (a == b && b == c) { Console.WriteLine(a); } else if(a == b || a == c) { var duplicates = abc.GroupBy(x => x).Where(x => x.Count() > 1).Select(x => x.Key).ToList(); var result = abc.Except(duplicates).ToList(); Console.WriteLine(String.Join("",result)); } else if(a != b && b != c) { Console.WriteLine(3); } } }