file = open('9.txt')
s = file.readline()
s = s.replace('B', 'A').replace('2', '1')
s = s.replace('11A', '*')
for i in range(len(s)):
    if s[i] != '*':
        s = s.replace(s[i], ' ')
s = s.split()
print(len(max(s, key = len)))