c1 = input()
c2 = input()

c = c1 + c2
cnt = 0
cnt_max = 0
for i in c:
    if (i == 'o'):
        cnt += 1
        
    if (i == 'x'):
        if(cnt_max < cnt):
            cnt_max = cnt
            
        cnt = 0
        
print(cnt_max)