M = input()
N = input()
O = M + N
O = list(O)
length = int(len(O)) - 1
array = []
count = 0
for i in range(0,14):
    if O[i] == "o" and int(i) == length:
        count += 1
        array.append(count)
    elif O[i] == "o" and O[i + 1] == "o":
        count += 1
    elif O[i] == "o" and O[i + 1] == "x":
        count += 1
        array.append(count)
    else:
        count = 0
array.sort()
array.reverse()
if array != []:
    print(array[0])
else:
    print("0")