Score : $300$ points

问题描述

在某个平行宇宙中，AtCoder 举办了一场 AtCoder 大赛，一次性给出了 $10^{16}$ 道题目。
这些题目的编号（ID）按照如下方式排列：A, B, ..., Z, AA, AB, ..., ZZ, AAA, ...

换句话说，题目的 ID 按照以下顺序给出：

• 长度为 $1$ 的由大写英文字母组成的字符串，按字典序排序；
• 长度为 $2$ 的由大写英文字母组成的字符串，按字典序排序；
• 长度为 $3$ 的由大写英文字母组成的字符串，按字典序排序；
• $...$

给定一个字符串 $S$，它是这场竞赛中某道题目的 ID，请找出该题目的索引位置。（参见示例部分）

以上为通义千问 qwen-max 翻译，仅供参考。

Problem Statement

In a parallel universe, AtCoder holds AtCoder Big Contest, where $10^{16}$ problems are given at once.
The IDs of the problems are as follows, from the $1$-st problem in order: A, B, ..., Z, AA, AB, ..., ZZ, AAA, ...

In other words, the IDs are given in the following order:

• the strings of length $1$ consisting of uppercase English letters, in lexicographical order;
• the strings of length $2$ consisting of uppercase English letters, in lexicographical order;
• the strings of length $3$ consisting of uppercase English letters, in lexicographical order;
• $...$

Given a string $S$ that is an ID of a problem given in this contest, find the index of the problem. (See also Samples.)

Constraints

• $S$ is a valid ID of a problem given in AtCoder Big Contest.

Input

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

$S$

Output

Print the answer as an integer.

Sample Input 1

AB

Sample Output 1

28

The problem whose ID is AB is the $28$-th problem of AtCoder Big Contest, so $28$ should be printed.

Sample Input 2

C

Sample Output 2

3

The problem whose ID is C is the $3$-rd problem of AtCoder Big Contest, so $3$ should be printed.

Sample Input 3

BRUTMHYHIIZP

Sample Output 3

10000000000000000

The problem whose ID is BRUTMHYHIIZP is the $10^{16}$-th (last) problem of AtCoder Big Contest, so $10^{16}$ should be printed as an integer.

update @ 2024/3/10 11:55:25