code

using System;
namespace hello
{
    class hello
    {
        static void Main(string[] args)
        {
            int age = 0; int c_year = 0; int c_hap_m_d = 0; int man_age = 0;
            string this_year = ""; string gender2 = "";

            Console.WriteLine("주민번호 13자리를 입력하세요");
            string s = Console.ReadLine();

            int year = int.Parse(s.Substring(0, 2));
            int month = int.Parse(s.Substring(2, 2));
            int day = int.Parse(s.Substring(4, 2));
            int gender = int.Parse(s.Substring(6, 1));
            int hap_m_d = int.Parse(s.Substring(2, 4));

            this_year = Convert.ToString(DateTime.Now);
            c_year = int.Parse(this_year.Substring(0, 4));
            c_hap_m_d= int.Parse(this_year.Substring(5, 2)+this_year.Substring(8,2));
            year = Calc_Year(year, gender);
            age = Calc_Age(year, c_year);
            gender2 = Calc_Gender(gender);
            man_age = Calc_Man_Age(hap_m_d, c_hap_m_d, year, c_year);

            Console.WriteLine("년도는 : {0}", year);
            Console.WriteLine("월은 {0}", month);
            Console.WriteLine("일은 {0}", day);
            Console.WriteLine("올해 나이는 {0}", age);
            Console.WriteLine("만 나이는 {0}", man_age);
            Console.WriteLine("성별은 {0}", gender2);
        }
        

        public static int Calc_Year(int a1, int b1)
        {
            int hap = 0;
            if(b1 == 3 || b1 == 4)
            {
                hap = 2000 + a1;
            }
            else
            {
                hap = 1900 + a1;
            }

            return hap;
        }
        public static int Calc_Age(int a2, int b2)
        {
            int age2 = b2 - a2 + 1;
            return age2;
        }

        public static string Calc_Gender(int a3)
        {
            string G = "";
            if(a3%2==1)
            {
                G = "남자";
            }
            else
            {
                G = "여자";
            }

            return G;
        }

        public static int Calc_Man_Age(int a4, int b4, int c4, int d4)
        {
            int MA = 0;
            if(b4>=a4)
            {
                MA = d4 - c4;
            }
            else
            {
                MA = d4 - c4 - 1;
            }

            return MA;
        }
    }
}