def resolve():
    s = input()
    print("YES" if s.count("o") + 15 - len(s) >= 8 else "NO")


if __name__ == "__main__":
    resolve() def resolve():
    s = input()
    print("YES" if s.count("o") + 15 - len(s) >= 8 else "NO") resolve s = input() s input() input print("YES" if s.count("o") + 15 - len(s) >= 8 else "NO") print "YES" if s.count("o") + 15 - len(s) >= 8 else "NO" s.count("o") + 15 - len(s) >= 8 s.count("o") + 15 - len(s) s.count("o") + 15 s.count("o") s.count s count "o" 15 len(s) len s 8 "YES" "NO" if __name__ == "__main__":
    resolve() __name__ == "__main__" __name__ "__main__" resolve() resolve def resolve():
    s = input()
    print("YES" if s.count("o") + 15 - len(s) >= 8 else "NO") def resolve():
    s = input()
    print("YES" if s.count("o") + 15 - len(s) >= 8 else "NO") resolve
def resolve():
    s = input()
    print("YES" if s.count("o") + 15 - len(s) >= 8 else "NO")


if __name__ == "__main__":
    resolve()
