输入一个正整数，经过几次运算直到结果得到1为止

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ConsoleApplication3
{
    class Program
    {
        static void Main(string[] args)
        {
            double integer=0,result=0;     //integer:正整数;
            Console.WriteLine("请输入一个正整数");
            integer = Convert.ToDouble(Console.ReadLine());
            do
            {
                Console.Write("第{0}次{1}------->", result, integer);
                if (integer % 2 == 0) integer /= 2;
                else integer=integer*3+1;

                result++;
                Console.WriteLine("{0}", integer);

            } while (integer!=1);
            Console.WriteLine("经过{0}次这样的运算才得到数1", result);
            Console.Read();

        }
    }
}