#-*- coding: utf-8
#  -*-
"""
oj dl https://atcoder.jp/contests/abc116/tasks/abc116_d -d test-d
oj test -d test-d -c "python abc116d.py"
oj test -d test-d -c "python abc116d.py" test-d/sample-3.in
"""
from collections import defaultdict
import sys
import math
from datetime import datetime

def sol(S):
    # oxoxoxoxoxoxox
    c = 0
    for s in S:
        if s == 'o': c+=1
    return 'YES' if 15 - len(S) + c >= 8 else 'NO'


do_submit = True
#do_submit = False

def input_parse(input_str):
    lines = [x.strip() for x in input_str.split("\n") if x.strip()]
    parsed_lines = [list(map(str, line.split())) for line in lines]
    print(parsed_lines)
    #n = int(parsed_lines[0][0])
    S = parsed_lines[0][0]
    # k = int(parsed_lines[0][1])
    # S = parsed_lines[1][0]
    # return n, k, S
    return S


if not do_submit:
    S = input_parse("""
    oxoxoxoxoxoxox
    """)
    print(sol(S))

    S = input_parse("""
    xxxxxxxx
    """)
    print(sol(S))

else:
    # n, k = list(map(int, input().split()))
    # S = input().split()
    # print(sol(n, k, S))
    S = input().strip()
    # S = input().strip()
    print(sol(S))
 """
oj dl https://atcoder.jp/contests/abc116/tasks/abc116_d -d test-d
oj test -d test-d -c "python abc116d.py"
oj test -d test-d -c "python abc116d.py" test-d/sample-3.in
""" from collections import defaultdict import sys sys import math math from datetime import datetime def sol(S):
    # oxoxoxoxoxoxox
    c = 0
    for s in S:
        if s == 'o': c+=1
    return 'YES' if 15 - len(S) + c >= 8 else 'NO' sol c = 0 c 0 for s in S:
        if s == 'o': c+=1
     s S if s == 'o': c+=1
     s == 'o' s 'o' return 'YES' if 15 - len(S) + c >= 8 else 'NO' 'YES' if 15 - len(S) + c >= 8 else 'NO' 15 - len(S) + c >= 8 15 - len(S) + c 15 - len(S) 15 len(S) len S c 8 'YES' 'NO' S S do_submit = True do_submit True def input_parse(input_str):
    lines = [x.strip() for x in input_str.split("\n") if x.strip()]
    parsed_lines = [list(map(str, line.split())) for line in lines]
    print(parsed_lines)
    #n = int(parsed_lines[0][0])
    S = parsed_lines[0][0]
    # k = int(parsed_lines[0][1])
    # S = parsed_lines[1][0]
    # return n, k, S
    return S input_parse x.strip() for x in input_str.split("\n") if x.strip() for x in input_str.split("\n") if x.strip() x input_str.split("\n") input_str.split input_str split "\n" x.strip() x.strip x strip if x.strip() x.strip() x.strip x strip lines = [x.strip() for x in input_str.split("\n") if x.strip()] lines [x.strip() for x in input_str.split("\n") if x.strip()] list(map(str, line.split())) for line in lines for line in lines line lines for line in lines list(map(str, line.split())) list map(str, line.split()) map str line.split() line.split line split parsed_lines = [list(map(str, line.split())) for line in lines] parsed_lines [list(map(str, line.split())) for line in lines] print(parsed_lines) print parsed_lines S = parsed_lines[0][0] S parsed_lines[0][0] [0] parsed_lines 0 0 return S S input_str input_str if not do_submit:
    S = input_parse("""
    oxoxoxoxoxoxox
    """)
    print(sol(S))

    S = input_parse("""
    xxxxxxxx
    """)
    print(sol(S))

else:
    # n, k = list(map(int, input().split()))
    # S = input().split()
    # print(sol(n, k, S))
    S = input().strip()
    # S = input().strip()
    print(sol(S)) not do_submit do_submit S = input_parse("""
    oxoxoxoxoxoxox
    """) S input_parse("""
    oxoxoxoxoxoxox
    """) input_parse """
    oxoxoxoxoxoxox
    """ print(sol(S)) print sol(S) sol S S = input_parse("""
    xxxxxxxx
    """) S input_parse("""
    xxxxxxxx
    """) input_parse """
    xxxxxxxx
    """ print(sol(S)) print sol(S) sol S S = input().strip() S input().strip() ().strip () input strip print(sol(S)) print sol(S) sol S S = input_parse("""
    oxoxoxoxoxoxox
    """) input_parse("""
    oxoxoxoxoxoxox
    """) S def input_parse(input_str):
    lines = [x.strip() for x in input_str.split("\n") if x.strip()]
    parsed_lines = [list(map(str, line.split())) for line in lines]
    print(parsed_lines)
    #n = int(parsed_lines[0][0])
    S = parsed_lines[0][0]
    # k = int(parsed_lines[0][1])
    # S = parsed_lines[1][0]
    # return n, k, S
    return S def input_parse(input_str):
    lines = [x.strip() for x in input_str.split("\n") if x.strip()]
    parsed_lines = [list(map(str, line.split())) for line in lines]
    print(parsed_lines)
    #n = int(parsed_lines[0][0])
    S = parsed_lines[0][0]
    # k = int(parsed_lines[0][1])
    # S = parsed_lines[1][0]
    # return n, k, S
    return S input_parse do_submit = True True do_submit def sol(S):
    # oxoxoxoxoxoxox
    c = 0
    for s in S:
        if s == 'o': c+=1
    return 'YES' if 15 - len(S) + c >= 8 else 'NO' def sol(S):
    # oxoxoxoxoxoxox
    c = 0
    for s in S:
        if s == 'o': c+=1
    return 'YES' if 15 - len(S) + c >= 8 else 'NO' sol S = input().strip() input().strip() S S = input_parse("""
    xxxxxxxx
    """) input_parse("""
    xxxxxxxx
    """) S
#-*- coding: utf-8
#  -*-
"""
oj dl https://atcoder.jp/contests/abc116/tasks/abc116_d -d test-d
oj test -d test-d -c "python abc116d.py"
oj test -d test-d -c "python abc116d.py" test-d/sample-3.in
"""
from collections import defaultdict
import sys
import math
from datetime import datetime

def sol(S):
    # oxoxoxoxoxoxox
    c = 0
    for s in S:
        if s == 'o': c+=1
    return 'YES' if 15 - len(S) + c >= 8 else 'NO'


do_submit = True
#do_submit = False

def input_parse(input_str):
    lines = [x.strip() for x in input_str.split("\n") if x.strip()]
    parsed_lines = [list(map(str, line.split())) for line in lines]
    print(parsed_lines)
    #n = int(parsed_lines[0][0])
    S = parsed_lines[0][0]
    # k = int(parsed_lines[0][1])
    # S = parsed_lines[1][0]
    # return n, k, S
    return S


if not do_submit:
    S = input_parse("""
    oxoxoxoxoxoxox
    """)
    print(sol(S))

    S = input_parse("""
    xxxxxxxx
    """)
    print(sol(S))

else:
    # n, k = list(map(int, input().split()))
    # S = input().split()
    # print(sol(n, k, S))
    S = input().strip()
    # S = input().strip()
    print(sol(S))

