using System;

using System.Linq;

public class Program

{

    public static void Main()

    {

            string S = "BAONXXOLL"; //1

            var newWord = countBallon(S);

​

            Console.WriteLine(newWord);

            S = "BAOOLLNNOLOLGBAX"; //2

            newWord = countBallon(S);

​

            Console.WriteLine(newWord);

            S = "rookiemistakes"; //0

            newWord = countBallon(S);

​

            Console.WriteLine(newWord);

    }

        static int countBallon(string S)

        {

            string BALLOON = "BALLOON";

            int count = 0;

            foreach (var letter in BALLOON)

            {

                var matches = S.Count(x => x == letter);

​

                count += matches;

​

            }

​

​

            if (count == 0)

            {

                return 0;

            }

            else if (count % 2 == 0)

            {

                return (count / BALLOON.Length) - 1;

​

            }

​

            else

            {

                return count / BALLOON.Length;

            }

​

        }

}