len, max = 0, 0
for i = 1, 2 do
    s = io.read()
    for j = 1, 7 do
        a = string.sub(s, j, j)
        if(a == "x") then max, len = math.max(max, len), 0 else len = len + 1 end
    end
end
max = math.max(max, len)
print(max)