import java.util.Scanner;

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

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String s = sc.next();
        int a = s.indexOf("A");
        int z = s.lastIndexOf("Z");
        System.out.println(z - a + 1);
    }
}
