Problem Description

A yahoo-type string is a string that starts with yah followed by the same lowercase English letter repeated twice. For example, yahoo and yahhh are yahoo-type strings, but yahoy and snuke are not.

Given a string \( S \) consisting of 5 lowercase English letters, determine whether it is a yahoo-type string.

Input Format

The input is given from the standard input in the following format:

\( S \)

Output Format

Output YES if \( S \) is a yahoo-type string, otherwise output NO.

Sample Input and Output

Sample Input #1

yahoo

Sample Output #1

YES

Sample Input #2

snuke

Sample Output #2

NO

Sample Input #3

yyyyy

Sample Output #3

NO

Notes/Hints

Constraints

• \( |S|=5 \)
• \( S \) consists of lowercase English letters

Sample Explanation 1

yahoo is a yahoo-type string.

Sample Explanation 2

snuke is not a yahoo-type string.

见题面 Input 部分

见题面 Output 部分