Problem:
Score : 200 points

Problem Statement

Snuke has decided to construct a string that starts with A and ends with Z, by taking out a substring of a string s (that is, a consecutive part of s).

Find the greatest length of the string Snuke can construct. Here, the test set guarantees that there always exists a substring of s that starts with A and ends with Z.

Constraints

1 ≦ |s| ≦ 200{,}000

s consists of uppercase English letters.

There exists a substring of s that starts with A and ends with Z.

Input

The input is given from Standard Input in the following format:

s

Output

Print the answer.

Sample Input 1

QWERTYASDFZXCV

Sample Output 1

5

By taking out the seventh through eleventh characters, it is possible to construct ASDFZ, which starts with A and ends with Z.

Sample Input 2

ZABCZ

Sample Output 2

4

Sample Input 3

HASFJGHOGAKZZFEGA

Sample Output 3

12

Solution in OCaml (4.10.0) (judge verdict: Accepted)

Scanf.scanf "%s" (fun s ->
    let n = String.length s in
    let rec loop i mi mx =
        if i = n then mx - mi + 1 else
            if s.[i] = 'Z' then loop (i + 1) mi i else
            if s.[i] = 'A' then loop (i + 1) (min mi i) mx else
                loop (i + 1) mi mx
    in
    loop 0 max_int 0 |> Printf.printf "%d\n"
)