file = open('25.txt')
s = file.readline()
s = s.replace('CA', '**')
for i in range(1, len(s)):
    if s[i] == 'C':
        if s[i-1] == '*':
            s = s.replace(s[i], '*')
        else:
            s = s.replace(s[i], ' ')
    if s[i] != '*' and s[i] != 'C':
        s = s.replace(s[i], ' ')
s = s.split()
print(len(max(s, key = len)))