Submission #886144

#	Time	Username	Problem	Language	Result	Execution time	Memory
886144		vjudge1	Airplane (NOI23_airplane)	C++17	100 / 100	352 ms	21112 KiB

Main

#include <bits/stdc++.h>

using namespace std;

template<typename A, typename B>
string to_string(pair<A, B>);
string to_string(string S) {
  return '"' + S + '"';
}
string to_string(const char* c) {
  return to_string(string(c));
}
string to_string(bool b) {
  return (b ? "true" : "false");
}
template<size_t T>
string to_string(bitset<T> bs) {
  return bs.to_string();
}
string to_string(vector<bool> v) {
  string res = "{";
  for (int i = 0; i < int(v.size()); ++i) {
    if (int(res.size()) > 1) {
      res += ", ";
    }
    res += to_string(v[i]);
  }
  return res + "}";
}
template<typename T>
string to_string(T v) {
  string res = "{";
  for (auto e : v) {
    if (int(res.size()) > 1) {
      res += ", ";
    }
    res += to_string(e);
  }
  return res + "}";
}
template<typename A, typename B>
string to_string(pair<A, B> p) {
  return '(' + to_string(p.first) + ", " + to_string(p.second) + ')';
}
void debug_out() {
  cerr << endl;
}
template<typename H, typename... T>
void debug_out(H head, T... tail) {
  cerr << "  " << to_string(head);
  debug_out(tail...);
}

#ifdef DEBUG 
  #define debug(...) cerr << "[" << #__VA_ARGS__ << "]:", debug_out(__VA_ARGS__) 
#else 
  #define debug(...) void(37)
#endif

template<typename T>
using min_pq = priority_queue<T, vector<T>, greater<T>>;

int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  int N, M;
  cin >> N >> M;
  vector<int> A(N);
  for (int i = 0; i < N; ++i) {
    cin >> A[i];
  }
  vector<vector<int>> g(N);
  for (int i = 0; i < M; ++i) {
    int X, Y;
    cin >> X >> Y;
    --X, --Y;
    g[X].push_back(Y);
    g[Y].push_back(X);
  }
  auto Sp = [&](int source) {
    vector<int> d(N, -1);
    min_pq<pair<int, int>> pq;
    auto Add = [&](int x, int nd) {
      nd = max(nd, A[x]);
      if (d[x] == -1 || nd < d[x]) {
        d[x] = nd;
        pq.emplace(nd, x);
      }
    };
    Add(source, 0);
    while (!pq.empty()) {
      auto[dist, v] = pq.top();
      pq.pop();
      if (d[v] < dist) {
        continue;
      }
      for (auto u : g[v]) {
        Add(u, dist + 1);
      }
    }
    return d;
  };
  auto d_s = Sp(0);
  auto d_t = Sp(N - 1);
  int ans = int(1e9);
  for (int i = 0; i < N; ++i) {
    ans = min(ans, max(d_s[i], d_t[i]) * 2);
    for (auto u : g[i]) {
      if (d_s[i] == d_t[u]) {
        ans = min(ans, d_s[i] * 2 + 1);
      }
    }
  }
  cout << ans << '\n';
}

• Subtask 1: 22 / 22
• Subtask 2: 10 / 10
• Subtask 3: 31 / 31
• Subtask 4: 37 / 37