using System;
public  class MathTest{
    private static void Main(){
        string num = Console.ReadLine();
        string input = Console.ReadLine();
        string replacestr = "vk";
        int output = 0;
        if(input.Contains(replacestr)){
            string replaced = input.Replace(replacestr," ");
            output+=input.Length - replaced.Length;
        }
        input = input.Replace(replacestr," ");
        if(input.Contains("vv")||input.Contains("kk")){
            output+=1;
        }
        Console.WriteLine("{0:0}"output);
    }
}