#pragma GCC diagnostic ignored "-Wmisleading-indentation"
#include <algorithm>
#include <iostream>
#include <numeric>
#include <cstring>
#include <iomanip>
#include <vector>
#include <bitset>
#include <stack>
#include <queue>
#include <cmath>
#include <set>
#include <map>
using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<int, int> pii;
const int maxn = 3e5+10;
const int lgmx = 20;
int rnk[lgmx][maxn*2];
int P[maxn*2];
int on[maxn*2];
int st[2];
int sz[2];
char S[maxn*2];
int ss = 0;
int f, pw;
int sfxa[maxn*2];
int lcpa[maxn*2];
int rev[maxn*2];
int L[maxn*2];
int R[maxn*2];
inline bool cmp(int i, int j)
{
if(rnk[f-1][i] < rnk[f-1][j]) return true;
if(rnk[f-1][i] > rnk[f-1][j]) return false;
int a = -1;
int b = -1;
if( i+pw < st[on[i]]+sz[on[i]] ) a = rnk[f-1][i+pw];
if( j+pw < st[on[j]]+sz[on[j]] ) b = rnk[f-1][j+pw];
return a < b;
}
inline int lcp(int i, int j)
{
if(i == j) return st[on[i]]+sz[on[i]]-i;
int m = 0;
for(int k = lgmx-1; k >= 0; k--)
{
int x = (1<<k);
if(i+m+x <= st[on[i]]+sz[on[i]] and j+m+x <= st[on[j]]+sz[on[j]])
if(rnk[k][i+m] == rnk[k][j+m])
m += x;
}
return m;
}
inline void bsfxa()
{
iota(P, P+ss, 0);
sort(P, P+ss, [&](int i, int j){return S[i] < S[j];});
rnk[0][P[0]] = 0;
for(int i = 1; i < ss; i++)
rnk[0][P[i]] = rnk[0][P[i-1]] + (S[P[i]] != S[P[i-1]]);
for(f = 1, pw = 1; f < lgmx; f++, pw*=2)
{
sort(P, P+ss, cmp);
rnk[f][P[0]] = 0;
for(int i = 1; i < ss; i++)
rnk[f][P[i]] = rnk[f][P[i-1]] + cmp(P[i-1], P[i]);
}
iota(sfxa, sfxa+ss, 0);
sort(sfxa, sfxa+ss, [&](int i, int j){return rnk[lgmx-1][i] < rnk[lgmx-1][j];});
for(int i = 1; i < ss; i++)
lcpa[i] = lcp(sfxa[i], sfxa[i-1]);
for(int i = 0; i < ss; i++)
rev[sfxa[i]] = i;
lcpa[0] = -1;
lcpa[ss] = -1;
L[0] = L[ss] = 0;
R[0] = R[ss] = ss;
for(int i = 1; i < ss; i++) for(L[i] = i-1; lcpa[L[i]] >= lcpa[i]; L[i] = L[L[i]]);
for(int i = ss-1; i > 0; i--) for(R[i] = i+1; lcpa[R[i]] >= lcpa[i]; R[i] = R[R[i]]);
//
}
int mr[maxn]; // practically lcp(sfxa[rev[i]], sfxa[rev[i]-1]) + i
int mc[maxn]; //
int mpl[maxn]; // max palindrome (even/odd)
int mjm[lgmx][maxn]; // j-mpl[j] (min)
ll ans = 0;
inline int getmn(int l, int r) // [l, r)
{
int k = __lg(r-l);
return min(mjm[k][l], mjm[k][r-(1<<k)]);
}
inline int mxpl(int l, int r) // [l, r)
{
if(r == l) return 0;
if(r-l == 1) return 0; // even
int i = l;
while(r-l > 1)
{
int k = __lg(r-l-1);
int m = r - (1<<k);
if(mjm[k][m] > i)
r = m;
else
l = m;
}
return l-i;
}
inline void pmjm(int n)
{
for(int k = 1; k < lgmx; k++)
{
int x = (1 << (k-1));
for(int i = 0; i < n; i++)
{
if(i+x < n)
mjm[k][i] = min(mjm[k-1][i], mjm[k-1][i+x]);
else
mjm[k][i] = mjm[k-1][i];
}
}
}
inline void calce(int n)
{
mpl[0] = 0;
mjm[0][0] = 0;
for(int i = 1; i < n; i++)
{
mpl[i] = lcp(i, ss-i);
mjm[0][i] = i-mpl[i];
}
pmjm(n);
for(int i = 0; i < n-1; i++)
ans = max(ans, 2ll*mxpl(i, (i+n)/2+1));
for(int i = 0; i < n; i++)
{
if(mr[i] == -1 or mr[i] == i or mr[i] == i+1) continue;
int x = mxpl(i, (i+mr[i])/2+1);
ans = max(ans, 2ll*mc[i]*x);
}
}
inline void calco(int n)
{
mpl[0] = 0;
mjm[0][0] = 0;
mpl[n-1] = 0;
mjm[0][n-1] = n-1;
for(int i = 1; i < n-1; i++)
{
mpl[i] = lcp(i+1, ss-i);
mjm[0][i] = i-mpl[i];
}
pmjm(n);
for(int i = 0; i < n-1; i++)
ans = max(ans, 2ll*mxpl(i, (i+n+1)/2)+1 );
for(int i = 0; i < n; i++)
{
if(mr[i] == -1 or mr[i] == i) continue;
int x = mxpl(i, (i+mr[i]+1)/2);
ans = max(ans, 2ll*mc[i]*x+mc[i]);
}
}
int32_t main()
{
ios::sync_with_stdio(false);
cin.tie(0);
string s;
cin >> s;
const int n = s.size();
if(n == 1)
{
cout << 1 << endl;
return 0;
}
fill(on, on+n, 0);
fill(on+n, on+n+n, 1);
st[0] = 0;
st[1] = n;
sz[0] = sz[1] = n;
ss = n;
for(int i = 0; i < n; i++)
S[i] = S[n+n-1-i] = s[i];
bsfxa();
//for(int i = 0; i < ss; i++) cerr << sfxa[i] << " "; cerr << endl;
//for(int i = 0; i < ss; i++) cerr << lcpa[i] << " "; cerr << endl;
//for(int i = 0; i < ss; i++) cerr << L[i] << " "; cerr << endl;
//for(int i = 0; i < ss; i++) cerr << R[i] << " "; cerr << endl;
mr[sfxa[0]] = -1;
mc[sfxa[0]] = -1;
for(int i = 1; i < n; i++)
{
int l = sfxa[i];
mr[l] = l+lcpa[i];
mc[l] = R[i]-L[i];
//cerr << l << ": " << mc[l] << " " << mr[l] << endl;
}
//
ss = n+n;
bsfxa();
calce(n);
calco(n);
cout << ans << endl;
return 0;
}
