s = input()

cnt = 0
for c in s:
    if c == 'x':
        cnt += 1
if cnt >= 8:
    print("NO")
else:
    print("YES")

# print(*data, sep='\n') s = input() s input() input cnt = 0 cnt 0 for c in s:
    if c == 'x':
        cnt += 1 c s if c == 'x':
        cnt += 1 c == 'x' c 'x' cnt += 1 cnt 1 if cnt >= 8:
    print("NO")
else:
    print("YES")

# print(*data, sep='\n') cnt >= 8 cnt 8 print("NO") print "NO" print("YES") print "YES" cnt = 0 0 cnt cnt += 1 1 cnt s = input() input() s
s = input()

cnt = 0
for c in s:
    if c == 'x':
        cnt += 1
if cnt >= 8:
    print("NO")
else:
    print("YES")

# print(*data, sep='\n')
