import java.util.*;
 
public class Main {
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        String a = sc.next();
        System.out.println(a.lastIndexOf('Z') - a.indexOf('A') + 1);
    }
} import java.util.*; util.* java public class Main {
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        String a = sc.next();
        System.out.println(a.lastIndexOf('Z') - a.indexOf('A') + 1);
    }
} Main public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        String a = sc.next();
        System.out.println(a.lastIndexOf('Z') - a.indexOf('A') + 1);
    } main {
        Scanner sc = new Scanner(System.in);
        String a = sc.next();
        System.out.println(a.lastIndexOf('Z') - a.indexOf('A') + 1);
    } Scanner sc = new Scanner(System.in); sc new Scanner(System.in) String a = sc.next(); a sc.next() sc.next sc System.out.println(a.lastIndexOf('Z') - a.indexOf('A') + 1) System.out.println System.out System System.out a.lastIndexOf('Z') - a.indexOf('A') + 1 a.lastIndexOf('Z') - a.indexOf('A') a.lastIndexOf('Z') a.lastIndexOf a 'Z' a.indexOf('A') a.indexOf a 'A' 1 String[] args args public class Main {
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        String a = sc.next();
        System.out.println(a.lastIndexOf('Z') - a.indexOf('A') + 1);
    }
} public class Main {
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        String a = sc.next();
        System.out.println(a.lastIndexOf('Z') - a.indexOf('A') + 1);
    }
} Main
import java.util.*;
 
public class Main {
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        String a = sc.next();
        System.out.println(a.lastIndexOf('Z') - a.indexOf('A') + 1);
    }
}