#include <bits/stdc++.h>
/// #include "AkbarKING.h"
#define int long long
#define endl '\n'
#define pii pair<int, int>
#define pb push_back
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
using namespace std;
const int sz = 2e5 + 9;
const int MOD = 1e9 + 7;
const int INF = 1e18;
signed main()
{
ios_base::sync_with_stdio(0);
cin.tie(nullptr);
string s;
cin >> s;
int n = s.size();
int total = 0;
vector<int> cnt(n + 5);
for (int fix = 0; fix < n; ++fix)
{
int l = fix, r = fix;
while(l >= 0 && r < n && s[l] == s[r])
{
++total;
++cnt[l];
--cnt[r + 1];
--l;
++r;
}
l = fix, r = fix + 1;
while(l >= 0 && r < n && s[l] == s[r])
{
++total;
++cnt[l];
--cnt[r + 1];
--l;
++r;
}
}
for (int i = 1; i < n; ++i)
{
cnt[i] += cnt[i - 1];
}
int res = total;
for (int pos = 0; pos < n; ++pos)
{
char tmp = s[pos];
for (char ch = 'a'; ch <= 'z'; ++ch)
{
s[pos] = ch;
int now = 0;
for (int i = 0; i < n; ++i)
{
for (int delta = 0; delta <= min(i, n - i - 1); ++delta)
{
if (s[i - delta] != s[i + delta])
{
break;
}
if (i - delta <= pos && pos <= i + delta)
{
++now;
}
}
}
for (int i = 0; i + 1 < n; ++i)
{
for (int delta = 0; delta <= min(i, n - i - 2); ++delta)
{
if (s[i - delta] != s[i + delta + 1])
{
break;
}
if (i - delta <= pos && pos <= i + delta + 1)
{
++now;
}
}
}
res = max(res, total - cnt[pos] + now);
}
s[pos] = tmp;
}
cout << res << '\n';
}
