'''
【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)