c1 = input()
c2 = input()
c = c1 + c2

ans = 0
cnt = 0
flag = False
for s in c:
    if s == 'o':
        if flag:
            cnt += 1
        else:
            flag = True
            cnt = 1
    else:
        cnt = 0
        flag = False
    ans = max(ans, cnt)

print(ans)