結果

問題 No.1778 括弧列クエリ / Bracketed Sequence Query
コンテスト
ユーザー miscalc
提出日時 2021-12-07 00:37:36
言語 C++17
(gcc 13.3.0 + boost 1.87.0)
結果
AC  
実行時間 824 ms / 2,000 ms
コード長 3,365 bytes
コンパイル時間 2,301 ms
コンパイル使用メモリ 209,356 KB
最終ジャッジ日時 2025-01-26 06:16:33
ジャッジサーバーID
（参考情報） 		judge2 / judge4
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 * 1
other AC * 27
権限があれば一括ダウンロードができます

ソースコード

diff # 

#include <bits/stdc++.h>
#include <atcoder/modint>
using namespace std;
using namespace atcoder;
//using mint = modint998244353;
using mint = modint1000000007;
using ll = long long;
using ld = long double;
using pll = pair<ll, ll>;
using tlll = tuple<ll, ll, ll>;
constexpr ll INF = 1LL << 60;
template<class T> bool chmin(T& a, T b) {if (a > b) {a = b; return true;} return false;}
template<class T> bool chmax(T& a, T b) {if (a < b) {a = b; return true;} return false;}
ll safemod(ll A, ll M) {return (A % M + M) % M;}
ll divfloor(ll A, ll B) {if (B < 0) {return divfloor(-A, -B);} return (A - safemod(A, B)) / B;}
ll divceil(ll A, ll B) {if (B < 0) {return divceil(-A, -B);} return divfloor(A + B - 1, B);}
#define FINALANS(A) do {cout << (A) << '\n'; exit(0);} while (false)

class lca
{
public:
  ll N, K;
  vector<vector<ll>> par;
  vector<ll> dist;
  vector<ll> v_dfs;
  vector<ll> i_dfs;

  void dfs(vector<vector<ll>> &G, ll v, ll pv)
  {
    par.at(0).at(v) = pv;
    dist.at(v) = (pv == -1 ? 0 : dist.at(pv) + 1);

    v_dfs.push_back(v);

    for (auto nv : G.at(v))
    {
      if (nv != pv)
        dfs(G, nv, v);
    }
  }

  lca(vector<vector<ll>> &G, ll root)
  {
    N = G.size();
    K = 1;
    ll tmp = 1;
    while (tmp < N)
    {
      tmp *= 2;
      K++;
    }

    par = vector<vector<ll>>(K, vector<ll>(N, -1));
    dist = vector<ll>(N, -1);

    dfs(G, root, -1);

    for (ll k = 0; k < K - 1; k++)
    {
      for (ll v = 0; v < N; v++)
      {
        if (par.at(k).at(v) == -1)
          par.at(k + 1).at(v) = -1;
        else
          par.at(k + 1).at(v) = par.at(k).at(par.at(k).at(v));
      }
    }

    i_dfs.resize(N);
    for (ll i = 0; i < N; i++)
    {
      i_dfs.at(v_dfs.at(i)) = i;
    }
  }

  ll query_ancestor(ll v, ll n)
  {
    for (ll k = K - 1; k >= 0; k--)
    {
      if (n & (1 << k))
        v = par.at(k).at(v);
      if (v == -1)
        return -1;
    }
    return v;
  }

  ll query_lca(ll u, ll v)
  {
    if (dist.at(u) < dist.at(v))
      swap(u, v);

    u = query_ancestor(u, dist.at(u) - dist.at(v));
    
    if (u == v)
      return u;
    for (ll k = K - 1; k >= 0; k--)
    {
      if (par.at(k).at(u) != par.at(k).at(v))
        u = par.at(k).at(u), v = par.at(k).at(v);
    }
    return par.at(0).at(u);
  }

  ll query_dist(ll u, ll v)
  {
    return dist.at(u) + dist.at(v) - 2 * dist.at(query_lca(u, v));
  }
};

int main()
{
  ll N, Q;
  cin >> N >> Q;
  string S;
  cin >> S;

  vector<pll> A;
  vector<ll> st;
  vector<ll> mpA(N);
  for (ll i = 0; i < N; i++)
  {
    if (S.at(i) == '(')
      st.push_back(i);
    else
    {
      mpA.at(st.back()) = A.size();
      mpA.at(i) = A.size();
      A.push_back(make_pair(st.back(), i));
      st.pop_back();
    }
  }
  A.push_back(make_pair(-1, -1));

  vector<vector<ll>> G(N / 2 + 1);
  vector<ll> st2;
  for (ll i = 0; i < N / 2 + 1; i++)
  {
    while (!st2.empty() && A.at(st2.back()).first > A.at(i).first)
    {
      G.at(st2.back()).push_back(i);
      G.at(i).push_back(st2.back());
      st2.pop_back();
    }
    st2.push_back(i);
  }

  lca lc(G, N / 2);
  for (ll q = 0; q < Q; q++)
  {
    ll x, y;
    cin >> x >> y;
    x--, y--;

    ll v = lc.query_lca(mpA.at(x), mpA.at(y));
    auto [ans1, ans2] = A.at(v);
    if (ans1 == -1)
      cout << -1 << '\n';
    else
      cout << ans1 + 1 << " " << ans2 + 1 << '\n';
  }
}
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