import re

s1 = input()
s2 = input()
s0 = s1 + s2

def max(a, b):
    return a if a >= b else b

holiday_list = re.findall(r'o+', s0)
maxday = 0

for cur in holiday_list:
    maxday = max(len(cur), maxday)
    
print(maxday)