using System;

public class Program

{

    public static void Main()

    {

        /** 

         * Given a string, write a method that counts its number of words. 

         * Assume there are no leading and trailing whitespaces and there 

         * is only single whitespace between two consecutive words.

         */

        Console.WriteLine(NumberOfWords("This is sample sentence"));        // 4 

        Console.WriteLine(NumberOfWords("OK"));     // 1 

        Console.WriteLine(NumberOfWords("Mauris consectetur urna sit amet risus ultricies rutrum."));       // 8 

        Console.WriteLine(NumberOfWords("Quisque M"));          // 2 

        Console.WriteLine(NumberOfWords("Xor"));        // 1 

    }

    public static int MyNumberOfWords(string str)

    {

        return str.Trim().Split(" ").Length;

    }

    public static int NumberOfWords(string str)

    {

        int numWords = 0;

        for (int i = 1; i < str.Length; i++) 

        {

            numWords = (char.IsWhiteSpace(str[i]) ? numWords + 1 : numWords);

        }

        return numWords + 1;

    }

}