結果

問題 No.3148 Min-Cost Destruction of Parentheses
コンテスト
ユーザー hos.lyric
提出日時 2025-05-16 21:59:37
言語 C++14
(gcc 13.3.0 + boost 1.87.0)
結果
AC  
実行時間 76 ms / 4,000 ms
コード長 4,610 bytes
コンパイル時間 1,174 ms
コンパイル使用メモリ 123,504 KB
実行使用メモリ 17,336 KB
最終ジャッジ日時 2025-05-16 21:59:42
合計ジャッジ時間 3,828 ms
ジャッジサーバーID
（参考情報） 		judge5 / judge2
このコードへのチャレンジ
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ファイルパターン 結果
sample AC * 3
other AC * 31
権限があれば一括ダウンロードができます
コンパイルメッセージ
main.cpp: In function ‘int main()’:
main.cpp:138:10: warning: ignoring return value of ‘int scanf(const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
  138 |     scanf("%s", S);
      |     ~~~~~^~~~~~~~~
main.cpp:141:12: warning: ignoring return value of ‘int scanf(const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
  141 |       scanf("%lld", &A[u]);
      |       ~~~~~^~~~~~~~~~~~~~~

ソースコード

diff # 

#include <cassert>
#include <cmath>
#include <cstdint>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <algorithm>
#include <bitset>
#include <chrono>
#include <complex>
#include <deque>
#include <functional>
#include <iostream>
#include <limits>
#include <map>
#include <numeric>
#include <queue>
#include <random>
#include <set>
#include <sstream>
#include <string>
#include <unordered_map>
#include <unordered_set>
#include <utility>
#include <vector>

using namespace std;

using Int = long long;

template <class T1, class T2> ostream &operator<<(ostream &os, const pair<T1, T2> &a) { return os << "(" << a.first << ", " << a.second << ")"; };
template <class T> ostream &operator<<(ostream &os, const vector<T> &as) { const int sz = as.size(); os << "["; for (int i = 0; i < sz; ++i) { if (i >= 256) { os << ", ..."; break; } if (i > 0) { os << ", "; } os << as[i]; } return os << "]"; }
template <class T> void pv(T a, T b) { for (T i = a; i != b; ++i) cerr << *i << " "; cerr << endl; }
template <class T> bool chmin(T &t, const T &f) { if (t > f) { t = f; return true; } return false; }
template <class T> bool chmax(T &t, const T &f) { if (t < f) { t = f; return true; } return false; }
#define COLOR(s) ("\x1b[" s "m")


// par: must represent a forest.
//   The roots should point to -1 or n.
// T: monoid
//   T()  should return the identity.
//   T::append(const T &t)  should multiply t from right.
//   T::operator<(const T &t)  should represent the order to optimize.
//     Small to large.
//     It must be a weak order (for the possible products of ts).
template <class T>
struct ForestOptimalOrder {
  int n;
  bool isForest;
  T total;
  vector<int> us;
  ForestOptimalOrder() : n(0), isForest(false), total() {}
  ForestOptimalOrder(const vector<int> &par, vector<T> ts)
      : n(par.size()), isForest(false), total() {
    assert(n == static_cast<int>(ts.size()));
    uf.assign(n + 1, -1);
    std::priority_queue<Entry> que;
    vector<int> tails(n + 1, n), nxt(n + 1, -1);
    for (int u = 0; u < n; ++u) que.push(Entry{ts[u], u, tails[u] = u});
    for (; !que.empty(); ) {
      const int v = que.top().head, tail = que.top().tail;
      que.pop();
      if (tails[v] == tail) {
        // v as early as possible ==> right after its parent
        const int u = root((~par[v]) ? par[v] : n);
        if (!connect(u, v)) return;
        nxt[tails[u]] = v; tails[u] = tail;
        if (u == n) {
          total.append(ts[v]);
        } else {
          ts[u].append(ts[v]);
          que.push(Entry{ts[u], u, tails[u]});
        }
      }
    }
    isForest = true;
    us.resize(n);
    for (int j = 0, u = n; j < n; ++j) us[j] = u = nxt[u];
  }

  struct Entry {
    T t;
    int head, tail;
    // reversed order
    bool operator<(const Entry &e) const { return (e.t < t); }
  };

  vector<int> uf;
  int root(int u) {
    return (uf[u] < 0) ? u : (uf[u] = root(uf[u]));
  }
  // root(u) becomes the parent
  bool connect(int u, int v) {
    u = root(u);
    v = root(v);
    if (u == v) return false;
    uf[u] += uf[v];
    uf[v] = u;
    return true;
  }
};

////////////////////////////////////////////////////////////////////////////////

struct Info {
  // (weight, score) -> (weight + a, score + b * weight + c)
  Int a, b, c;
  Info() : a(0), b(0), c(0) {}
  void append(const Info &t) {
    b += t.b;
    c += t.b * a + t.c;
    a += t.a;
  }
  bool operator<(const Info &t) const {
    return (t.b * a < b * t.a);
  }
};


int N;
char S[200'010];
vector<Int> A;

vector<int> us, to;

vector<int> par;
void parse(int l, int r, int p) {
  for (int x = l; x < r; x = to[x] + 1) {
    const int u = us[x];
    par[u] = p;
    parse(x + 1, to[x], u);
  }
}

int main() {
  for (; ~scanf("%d", &N); ) {
    scanf("%s", S);
    A.resize(N);
    for (int u = 0; u < N; ++u) {
      scanf("%lld", &A[u]);
    }
    
    us.assign(2*N, -1);
    to.assign(2*N, -1);
    {
      vector<int> stack;
      int u = 0;
      for (int x = 0; x < 2*N; ++x) {
        if (S[x] == '(') {
          stack.push_back(x);
          us[x] = u++;
        } else {
          const int y = stack.back();
          stack.pop_back();
          to[y] = x;
          to[x] = y;
        }
      }
    }
    par.assign(N, -2);
    parse(0, 2*N, -1);
cerr<<"par = "<<par<<endl;
    
    vector<Info> ts(N);
    for (int u = 0; u < N; ++u) {
      ts[u].a = 1;
      ts[u].b = A[u];
      ts[u].c = 0;
    }
    const ForestOptimalOrder<Info> foo(par, ts);
cerr<<"foo.us = "<<foo.us<<endl;
    const Int ans = foo.total.b * 1 + foo.total.c;
    printf("%lld\n", ans);
  }
  return 0;
}
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