using System; using System.Collections; using System.Collections.Generic; using System.Collections.Specialized; using System.Text; using System.Text.RegularExpressions; using System.Linq; class Magatro { static void Main() { int min = 1; int max = 1000000000; while (true) { int aida = (min + max) / 2; Console.WriteLine("? {0}", aida); string ans = Console.ReadLine(); if (ans == "0") { min = aida+1; } else { max = aida; } if (min == max) { break; } } Console.WriteLine("! {0}", min); } }