using System; using System.Linq; namespace ConsoleApp1 { class Program { static void Main(string[] args) { var line1 = int.Parse(Console.ReadLine()); var n = line1; int result = 0; int biscuit = 1; while (true) { result++; biscuit = 2 * biscuit; if (biscuit >= n) { break; } } //結果を表示 Console.WriteLine(result); } } }