using System;

​

public class Program

{

    static  class Assert{

        static public void IsTrue(bool value){

            if(!value){

                Console.WriteLine("Expected True, but was False");

            }

        }

        static public void IsFalse(bool value){

            if(value){

                Console.WriteLine("Expected False, but was True");

            }

        }

    }

    static bool canUseES18(string userAgent){

        var result = true;

        var geckoType = userAgent.IndexOf("(KHTML, like Gecko) ");

        var version = 0;

            if(geckoType > 0){

                var chrome = userAgent.IndexOf("Chrome/", geckoType);

                if(chrome > 0){

                    chrome = chrome + 7;

                    version =  Int32.Parse(userAgent.Substring(chrome, userAgent.IndexOf(".", chrome) - chrome));

                    if(version < 64)

                        return false;

                }

                var safari = userAgent.IndexOf("Version/", geckoType);

                if(safari > 0){

                    safari = safari + 8;

                    version =  Int32.Parse(userAgent.Substring(safari, userAgent.IndexOf(".", safari) - safari));

                    if(version < 11)

                        return false;

                }

                // CriOS - crome под iOS. Информации по поддержке этим браузером named Groups нет. Отключаем для всех версий, младше 72 (так как получили ошибку от 71 версии) 

                var crios = userAgent.IndexOf("CriOS/", geckoType);

                if(crios > 0){

                    crios = crios + 6;

                    version =  Int32.Parse(userAgent.Substring(crios, userAgent.IndexOf(".", crios) - crios));

                    if(version < 72)

                        return false;

                }

            }else{

                var fireFox = userAgent.IndexOf("Firefox/");

                if(fireFox > 0 ){

                    fireFox = fireFox + 8;

                    version =  Int32.Parse(userAgent.Substring(fireFox, userAgent.IndexOf(".", fireFox) - fireFox));

                    if(version < 78)

                        return false;

                }

            }

        return result;

        }

    public static void Main()

    {

        // canUse. Используем новый синтаксис

        Assert.IsTrue(canUseES18("Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/95.0.4638.69 Safari/537.36"));

        Assert.IsTrue(canUseES18("Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/122.0.4638.69 Safari/537.36"));

        Assert.IsTrue(canUseES18("Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/96.0.4664.45 Safari/537.36"));

        Assert.IsTrue(canUseES18("Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/95.0.4638.69 Safari/537.36"));

        Assert.IsTrue(canUseES18("Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:94.0) Gecko/20100101 Firefox/94.0"));

        Assert.IsTrue(canUseES18("Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:94.0) Gecko/20100101 Firefox/78.0"));

        // cantUse. Используем старый синтаксис 

        Assert.IsFalse(canUseES18("Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/35.0.4638.69 Safari/537.36"));       

        Assert.IsFalse(canUseES18("Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/2.0.4638.69 Safari/537.36"));

        Assert.IsFalse(canUseES18("Mozilla/5.0 (Windows NT 6.2; WOW64) AppleWebKit/534.57.2 (KHTML, like Gecko) Version/5.1.7 Safari/534.57.2"));

        Assert.IsFalse(canUseES18("Mozilla/5.0 (iPad; CPU OS 10_3_4 like Mac OS X) AppleWebKit/603.3.8 (KHTML, like Gecko) Version/10.0 Mobile/14G61 Safari/602.1"));

        Assert.IsFalse(canUseES18("Mozilla/5.0 (iPad; CPU OS 10_3_3 like Mac OS X) AppleWebKit/603.3.8 (KHTML, like Gecko) Version/10.0 Mobile/14G60 Safari/602.1"));

        Assert.IsFalse(canUseES18("Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:94.0) Gecko/20100101 Firefox/77.0"));

        Assert.IsFalse(canUseES18("Mozilla/5.0 (iPad; CPU OS 10_3_4 like Mac OS X) AppleWebKit/603.1.30 (KHTML, like Gecko) CriOS/71.0.3578.89 Mobile/14G61 Safari/602.1"));

    }

}