101591: [AtCoder]ABC159 B - String Palindrome

Memory Limit:256 MB Time Limit:2 S
Judge Style:Text Compare Creator:
Submit:0 Solved:0

Description

Score : $200$ points

Problem Statement

A string $S$ of an odd length is said to be a strong palindrome if and only if all of the following conditions are satisfied:

  • $S$ is a palindrome.
  • Let $N$ be the length of $S$. The string formed by the $1$-st through $((N-1)/2)$-th characters of $S$ is a palindrome.
  • The string consisting of the $(N+3)/2$-st through $N$-th characters of $S$ is a palindrome.

Determine whether $S$ is a strong palindrome.

Constraints

  • $S$ consists of lowercase English letters.
  • The length of $S$ is an odd number between $3$ and $99$ (inclusive).

Input

Input is given from Standard Input in the following format:

$S$

Output

If $S$ is a strong palindrome, print Yes; otherwise, print No.


Sample Input 1

akasaka

Sample Output 1

Yes
  • $S$ is akasaka.
  • The string formed by the $1$-st through the $3$-rd characters is aka.
  • The string formed by the $5$-th through the $7$-th characters is aka. All of these are palindromes, so $S$ is a strong palindrome.

Sample Input 2

level

Sample Output 2

No

Sample Input 3

atcoder

Sample Output 3

No

Input

题意翻译

## 题目描述 一个长度为奇数的字符串 $S$ 被称为 $strong$ $palindrome$ 当且仅当以下几点全部满足。 - $S$ 是一个回文串。 - 设 $N$ 是 $S$ 的长度。$S$的前$(\frac{(N-1)}{2})$个字符所组成的字符串是回文的。 - $S$的后$(\frac{(N+3)}{2})$个字符所组成的字符串是回文的。 判断$S$是否是 $strong$ $palindrome$。 ## 输入格式 标准输入。 一行一个字符串 $S$。 ## 输出格式 如果 $S$ 是 $strong$ $palindrome$,输出 $Yes$;否则输出 $No$。 ## 数据范围 - $S$只包含小写字母。 - $S$的长度是一个属于$[3,99]$的奇数。

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