#coding: utf-8
#yuki_203

s1=raw_input()
s2=raw_input()
s=s1+s2
cnt=0
temp=0
for i in xrange(len(s)):
 if s[i]=="o":
  temp+=1
  if temp>cnt:
   cnt=temp
 elif s[i]=="x":
  temp=0
  
print cnt