Problem:
Score : 200 points

Problem Statement

Takahashi is competing in a sumo tournament.
The tournament lasts for 15 days, during which he performs in one match per day.
If he wins 8 or more matches, he can also participate in the next tournament.

The matches for the first k days have finished.
You are given the results of Takahashi's matches as a string S consisting of o and x.
If the i-th character in S is o, it means that Takahashi won the match on the i-th day; if that character is x, it means that Takahashi lost the match on the i-th day.

Print YES if there is a possibility that Takahashi can participate in the next tournament, and print NO if there is no such possibility.

Constraints

1 \leq k \leq 15

S is a string of length k consisting of o and x.

Input

Input is given from Standard Input in the following format:

S

Output

Print YES if there is a possibility that Takahashi can participate in the next tournament, and print NO otherwise.

Sample Input 1

oxoxoxoxoxoxox

Sample Output 1

YES

Takahashi has 7 wins and 7 losses before the last match. If he wins that match, he will have 8 wins.

Sample Input 2

xxxxxxxx

Sample Output 2

NO

Solution in C (Clang 3.8.0) (judge verdict: Accepted)

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int main(void){
   int k,i,countwin;
   char str[100],s[100],*p;

   fgets(str,sizeof(str),stdin);

   p=strtok(str," \n");
   strcpy(s,p);
   k=strlen(s);

   for(i=0,countwin=0;i<k;i++){
     if(s[i]=='o'){
         countwin++;
      }
   }
    if((15-k)+countwin>=8){
        printf("YES");
     }else{
         printf("NO");
      }

  return 0;
}