103380: [Atcoder]ABC338 A - Capitalized?

Problem Statement

You are given a non-empty string $S$ consisting of uppercase and lowercase English letters. Determine whether the following condition is satisfied:

• The first character of $S$ is uppercase, and all other characters are lowercase.

Constraints

• $1 \leq |S| \leq 100$ ($|S|$ is the length of the string $S$.)
• Each character of $S$ is an uppercase or lowercase English letter.

Input

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

$S$

Output

If the condition is satisfied, print Yes; otherwise, print No.

Sample Input 1

Capitalized

Sample Output 1

Yes

The first character C of Capitalized is uppercase, and all other characters apitalized are lowercase, so you should print Yes.

Sample Input 2

AtCoder

Sample Output 2

No

AtCoder contains an uppercase letter C that is not at the beginning, so you should print No.

Sample Input 3

yes

Sample Output 3

No

The first character y of yes is not uppercase, so you should print No.

Sample Input 4

A

Sample Output 4

Yes

问题描述

给你一个非空字符串 $S$，由大写和小写英文字母组成。确定以下条件是否满足：

• $S$ 的第一个字符是大写，所有其他字符都是小写。

约束

• $1 \leq |S| \leq 100$ ($|S|$ 是字符串 $S$ 的长度。)
• $S$ 的每个字符都是大写或小写英文字母。

输入

输入从标准输入按以下格式给出：

$S$

输出

如果条件满足，打印 Yes；否则，打印 No。

样例输入 1

Capitalized

样例输出 1

Yes

Capitalized 的第一个字符 C 是大写，所有其他字符 apitalized 都是小写，所以你应该打印 Yes。

样例输入 2

AtCoder

样例输出 2

No

AtCoder 包含一个不在开头的大写字母 C，所以你应该打印 No。

样例输入 3

yes

样例输出 3

No

yes 的第一个字符 y 不是大写，所以你应该打印 No。

样例输入 4

A

样例输出 4

Yes