Problem Description

Takahashi is participating in a sumo tournament. The tournament lasts for 15 days, and Takahashi competes in one match each day. Takahashi can participate in the next tournament if he wins at least 8 matches.

The matches up to day $ k $ have concluded. A string $ S $ of length $ k $ consisting of o and x is given, representing the results of Takahashi's matches. If the $ i $-th character of $ S $ is o, it means Takahashi won on day $ i $; if it is x, he lost.

Output YES if there is a possibility that Takahashi can participate in the next tournament; otherwise, output NO.

Input Format

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

$ S $

Output Format

Output YES if there is a possibility that Takahashi can participate in the next tournament; otherwise, output NO.

Sample Input and Output

Sample Input #1

oxoxoxoxoxoxox

Sample Output #1

YES

Sample Input #2

xxxxxxxx

Sample Output #2

NO

Notes/Hints

Constraints

• $1 \leq k \leq 15$
• $ S $ is a string of length $ k $ consisting of o and x

Sample Explanation 1

Takahashi has 7 wins and 7 losses after the 14th match, so he can achieve 8 wins if he wins the last match.

见题面 Input 部分

见题面 Output 部分