1 #include<iostream>
2 #include<algorithm>
3 #include<cstring>
4 using namespace std;
5
6 char ss[110005],s[220010];
7 int p[220010];
8
9 int init()
10 {
11 s[0]='$'; s[1]='#';
12 int g=2;
13 for(int i=0;ss[i]!='\0';i++)
14 {
15 s[g++]=ss[i];
16 s[g++]='#';
17 }
18 s[g]='\0';
19 return g; //·µ»Ø³¤¶È
20 }
21 int manacher()
22 {
23 int len =init();
24 int maxlen =-1;
25
26 int id;
27 int mx= 0;
28
29 for(int i=1;i<len;i++)
30 {
31 if(i<mx) p[i]=min( p[2*id-i], mx-i);
32 else p[i]=1;
33
34 while(s[i-p[i]] == s[i+p[i]] )
35 p[i]++;
36
37 if(i+p[i] > mx)
38 {
39 id=i;
40 mx=p[i]+i;
41 }
42 maxlen=max(maxlen,p[i]-1);
43 }
44 return maxlen;
45
46 }
47
48 int main()
49 {
50 ios::sync_with_stdio(false);
51 while(cin>>ss)
52 {
53 int res=manacher();
54 cout<<res<<endl;
55 }
56 }
