import java.util.*;
import java.lang.*;
import java.io.*;

class Ideone
{
    public static void main(String[] args) {
        System.out.println(countYZ("fez day"));
        System.out.println(countYZ("day fez"));
        System.out.println(countYZ("day fyyyz"));
    }

    public static int countYZ(String str) {
        String regex = "([yYzZ](?![A-Za-z]))|.";
        return str.toLowerCase().replaceAll(regex, "$1").length();
    }
}