[Link] https://www.acmicpc.net/problem/16163
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#include <algorithm>
#include <iostream>
#include <vector>
#include <map>
#include <set>
#include <queue>
#include <cstring>
#include <stack>
// #include <bits/stdc++.h>
using namespace std;
#define for0(i, n) for(int i = 0; i < n; i++)
#define for1(i, n) for(int i = 1; i < n; i++)
#define fori(s, e) for(int i = s; i < e; i++)
#define ll long long
#define endl "\n"
#define nulls '\0'
#define dkdk " "
const int MAX = 5e5 + 1;
const int INF = 987654321;
string s;
ll ans = 0;
void solve() {
int l_odd = 0, r_odd = -1;
int l_even = 0, r_even = -1;
vector<int> odd(s.size(), 1);
vector<int> even(s.size(), 0);
for(int i = 0; i < s.size(); i++) {
if(i <= r_odd) odd[i] = min(r_odd - i + 1, odd[l_odd+r_odd-i]);
if(i <= r_even) even[i] = min(r_even - i, even[l_even+r_even - i - 1]);
while(i-odd[i]>=0 && i+odd[i]<s.size() && s[i-odd[i]] == s[i+odd[i]]) odd[i]++;
while(i-even[i]>=0 && i+even[i]+1<s.size() && s[i-even[i]] == s[i+even[i]+1]) even[i]++;
if(i + odd[i] - 1 > r_odd) {
r_odd = i + odd[i] - 1;
l_odd = i - odd[i] + 1;
}
if(i + even[i] > r_even) {
r_even = i + even[i];
l_even = i + 1 - even[i];
}
ans += (odd[i] + even[i]);
}
}
int main() {
ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
cin >> s;
solve();
cout << ans;
return 0;
}