結果

問題 No.263 Common Palindromes Extra
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
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ソースコード

diff #

// 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;
}
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