S = input() + input()

K = []
A = 0

for i in range (len(S)):
    if i == 13 and S[13] == 'o':
        A += 1
        K.append(A)
    elif S[i] == 'o':
        A += 1
    else:
        K.append(A)
        A = 0

print(max(K))