結果
| 問題 |
No.263 Common Palindromes Extra
|
| コンテスト | |
| ユーザー |
 kuhaku
|
| 提出日時 | 2025-02-23 21:55:19 |
| 言語 | C++23 (gcc 13.3.0 + boost 1.87.0) |
| 結果 |
AC
|
| 実行時間 | 88 ms / 2,000 ms |
| コード長 | 6,398 bytes |
| コンパイル時間 | 4,573 ms |
| コンパイル使用メモリ | 324,768 KB |
| 実行使用メモリ | 65,540 KB |
| 最終ジャッジ日時 | 2025-02-23 21:55:25 |
| 合計ジャッジ時間 | 6,088 ms |
|
ジャッジサーバーID （参考情報） |
judge3 / judge5 |
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| ファイルパターン | 結果 |
|---|---|
| other | AC * 12 |
ソースコード
// competitive-verifier: PROBLEM https://yukicoder.me/problems/no/0263
#ifdef ATCODER
#pragma GCC target("sse4.2,avx512f,avx512dq,avx512ifma,avx512cd,avx512bw,avx512vl,bmi2")
#endif
#pragma GCC optimize("Ofast,fast-math,unroll-all-loops")
#include <bits/stdc++.h>
#ifndef ATCODER
#pragma GCC target("sse4.2,avx2,bmi2")
#endif
template <class T, class U>
constexpr bool chmax(T &a, const U &b) {
return a < (T)b ? a = (T)b, true : false;
}
template <class T, class U>
constexpr bool chmin(T &a, const U &b) {
return (T)b < a ? a = (T)b, true : false;
}
constexpr std::int64_t INF = 1000000000000000003;
constexpr int Inf = 1000000003;
constexpr double EPS = 1e-7;
constexpr double PI = 3.14159265358979323846;
#define FOR(i, m, n) for (int i = (m); i < int(n); ++i)
#define FORR(i, m, n) for (int i = (m)-1; i >= int(n); --i)
#define FORL(i, m, n) for (int64_t i = (m); i < int64_t(n); ++i)
#define rep(i, n) FOR (i, 0, n)
#define repn(i, n) FOR (i, 1, n + 1)
#define repr(i, n) FORR (i, n, 0)
#define repnr(i, n) FORR (i, n + 1, 1)
#define all(s) (s).begin(), (s).end()
struct Sonic {
Sonic() {
std::ios::sync_with_stdio(false);
std::cin.tie(nullptr);
std::cout << std::fixed << std::setprecision(20);
}
constexpr void operator()() const {}
} sonic;
using namespace std;
using ll = std::int64_t;
using ld = long double;
template <class T, class U>
std::istream &operator>>(std::istream &is, std::pair<T, U> &p) {
return is >> p.first >> p.second;
}
template <class T>
std::istream &operator>>(std::istream &is, std::vector<T> &v) {
for (T &i : v) is >> i;
return is;
}
template <class T, class U>
std::ostream &operator<<(std::ostream &os, const std::pair<T, U> &p) {
return os << '(' << p.first << ',' << p.second << ')';
}
template <class T>
std::ostream &operator<<(std::ostream &os, const std::vector<T> &v) {
for (auto it = v.begin(); it != v.end(); ++it) os << (it == v.begin() ? "" : " ") << *it;
return os;
}
template <class Head, class... Tail>
void co(Head &&head, Tail &&...tail) {
if constexpr (sizeof...(tail) == 0) std::cout << head << '\n';
else std::cout << head << ' ', co(std::forward<Tail>(tail)...);
}
template <class Head, class... Tail>
void ce(Head &&head, Tail &&...tail) {
if constexpr (sizeof...(tail) == 0) std::cerr << head << '\n';
else std::cerr << head << ' ', ce(std::forward<Tail>(tail)...);
}
void Yes(bool is_correct = true) { std::cout << (is_correct ? "Yes\n" : "No\n"); }
void No(bool is_not_correct = true) { Yes(!is_not_correct); }
void YES(bool is_correct = true) { std::cout << (is_correct ? "YES\n" : "NO\n"); }
void NO(bool is_not_correct = true) { YES(!is_not_correct); }
void Takahashi(bool is_correct = true) { std::cout << (is_correct ? "Takahashi" : "Aoki") << '\n'; }
void Aoki(bool is_not_correct = true) { Takahashi(!is_not_correct); }
/**
* @brief 回文木
* @see https://math314.hateblo.jp/entry/2016/12/19/005919
*/
struct palindromic_tree {
private:
struct _node {
using pointer = _node *;
std::map<char, int> link;
int suffix_link;
int len;
int count;
_node() : link(), suffix_link(), len(), count() {}
_node(int _suffix_link, int _len, int _count)
: link(), suffix_link(_suffix_link), len(_len), count(_count) {}
};
public:
using node_type = _node;
using node_pointer = typename _node::pointer;
palindromic_tree() : nodes(), str(), active_idx() {
create_node(0, -1, 0);
create_node(0, 0, 0);
}
int size() const { return nodes.size(); }
int get_active_idx() const { return active_idx; }
node_pointer get_node(int id) { return &nodes[id]; }
int add(char ch) {
str.push_back(ch);
int a = find_prev_palindrome_idx(active_idx);
auto inserted_result = nodes[a].link.insert(std::make_pair(ch, int(nodes.size())));
active_idx = inserted_result.first->second;
if (!inserted_result.second) {
nodes[active_idx].count++;
return active_idx;
}
node_pointer node = create_node(0, nodes[a].len + 2, 1);
if (node->len == 1) {
node->suffix_link = 1;
} else {
int b = find_prev_palindrome_idx(nodes[a].suffix_link);
node->suffix_link = nodes[b].link[ch];
}
return active_idx;
}
int move(char ch) {
str.push_back(ch);
while (true) {
active_idx = find_prev_palindrome_idx(active_idx);
auto it = nodes[active_idx].link.find(ch);
if (it != nodes[active_idx].link.end()) {
active_idx = it->second;
return active_idx;
}
if (active_idx == 0) break;
active_idx = nodes[active_idx].suffix_link;
}
return active_idx;
}
std::vector<int> build_frequency() {
std::vector<int> res(nodes.size());
for (int i = int(nodes.size()) - 1; i > 0; --i) {
res[i] += nodes[i].count;
res[nodes[i].suffix_link] += res[i];
}
return res;
}
void clear() {
str.clear();
active_idx = 0;
}
private:
std::vector<node_type> nodes;
std::string str;
int active_idx;
node_pointer create_node(int suffix_link, int len, int count) {
nodes.emplace_back(suffix_link, len, count);
return &nodes.back();
}
int find_prev_palindrome_idx(int node_id) {
int pos = int(str.size()) - 1;
while (true) {
int opposite_side_idx = pos - 1 - nodes[node_id].len;
if (opposite_side_idx >= 0 && str[opposite_side_idx] == str.back()) break;
node_id = nodes[node_id].suffix_link;
}
return node_id;
}
};
int main(void) {
std::string s, t;
std::cin >> s >> t;
palindromic_tree pt;
for (auto c : s) pt.add(c);
auto v = pt.build_frequency();
std::vector<std::int64_t> vs(v.begin(), v.end());
int m = vs.size();
for (int i = 0; i < m; ++i) {
if (i < 2)
continue;
int p = pt.get_node(i)->suffix_link;
if (p >= 2)
vs[i] += vs[p];
}
pt.clear();
std::int64_t ans = 0;
for (auto c : t) {
int idx = pt.move(c);
if (idx >= 2)
ans += vs[idx];
}
std::cout << ans << '\n';
return 0;
}