AgeAfterTenYears

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

class AgeAfterTenYears
{
    static void Main(string[] args)
    {
        Console.Write("Enter your birthday: ");
        string birsthdayStr = Console.ReadLine();
        DateTime birthday;
        int currentYear = DateTime.Now.Year;
        int yearOfBirth;
        int ageNow;
        int ageAfterTenYears;
        bool birthdayCorrectFormat = DateTime.TryParse(birsthdayStr, out birthday);
        if (birthdayCorrectFormat)
        {
            yearOfBirth = birthday.Year;
            DateTime birthdayThisYeas = new DateTime(currentYear, birthday.Month, birthday.Day);
            if (birthdayThisYeas > DateTime.Today)
            {
                ageNow = (currentYear - yearOfBirth) - 1;
            }
            else
            {
                ageNow = currentYear - yearOfBirth;
            }
            ageAfterTenYears = ageNow + 10;
            Console.WriteLine("Your age now: {0}. Your age after 10 years: {1}", ageNow, ageAfterTenYears);
        }
        else
        {
            Console.WriteLine("Wrong format of birthday.");
        }
    }
}