Bank Number Generator

using System;

namespace BankNumberGenerator
{
    internal class Program
    {
        static void Main(string[] args)
        {
            int a = int.Parse(Console.ReadLine());
            char b = char.Parse(Console.ReadLine());
            char c = char.Parse(Console.ReadLine());
            char d = char.Parse(Console.ReadLine());
            int e = int.Parse(Console.ReadLine());
            int n = int.Parse(Console.ReadLine());

            for (int i = a; i <= 99; i++)
            {
                for (char j = b; j <= 'Z'; j++)
                {
                    for (char k = c; k <= 'z'; k++)
                    {
                        for (char l = d; l <= 'Z'; l++)
                        {
                            for (int m = e; m >= 10; m--)
                            {
                                if (i % 10 == 2 && m % 10 == 5)
                                {
                                    n--;
                                    if (n == 0)
                                    {
                                        Console.WriteLine($"{i}{j}{k}{l}{m}");
                                        Environment.Exit(0);
                                    }
                                }
                            }
                        }
                    }
                }
            }
        }
    }
}