'''
【环形】-【连续】-【最大长度】-[连续字串[情况]]
---
线性连续
【线性】-[前缀+后缀]
拼接
'''
s = input().strip()
n = len(s)
if n ==1:
print(1)
else:
max_len = 1
current = 1
for i in range(1,n):
if s[i] == s[i-1]:
current += 1
#**【Q】 最长连续相同字符 当前连续长度
max_len = max(max_len,current)
else:
current = 1
pre = 1
for i in range (1,n):
if s[i] == s[0]:
pre += 1
else:
break
suf = 1
''' 字符串最后一个字母 索引是n-1
【左开右边【迁移】】
我们从倒数第二个字符开始比较'''
for i in range (n-2,-1,-1):
if s[i] == s[-1]:
suf += 1
else:
break
circle = 0
if s[0] == s[-1]:
circle = pre +suf
ans = min(max(max_len,circle),n)
print(ans)