Submission #1280871

#	Time	Username	Problem	Language	Result	Execution time	Memory
1280871		aeg	Airplane (NOI23_airplane)	C++20	100 / 100	223 ms	24516 KiB

Main

#include <bits/stdc++.h>
using namespace std;

#define int int64_t

signed main() {
  cin.tie(0)->sync_with_stdio(0);
  int n, m;
  cin >> n >> m;
  vector<int> a(n);
  for (auto &x : a)
    cin >> x;
  vector<vector<int>> adj(n, vector<int>());
  for (int i = 0; i < m; i++) {
    int x, y;
    cin >> x >> y;
    x--;
    y--;
    adj[x].push_back(y);
    adj[y].push_back(x);
  }

  vector<int> dist(n, INT64_MAX);
  dist[0] = 0;
  vector<int> ndist(n, INT64_MAX);
  ndist[n - 1] = 0;

  priority_queue<pair<int, int>, vector<pair<int, int>>,
                 greater<pair<int, int>>>
      pq;

  pq.emplace(0, 0);
  while (!pq.empty()) {
    auto [dt, s] = pq.top();
    pq.pop();

    for (int x : adj[s]) {
      if (dist[x] > max(dt + 1, a[x])) {
        dist[x] = max(dt + 1, a[x]);
        pq.emplace(dist[x], x);
      }
    }
  }

  pq.emplace(0, n - 1);
  while (!pq.empty()) {
    auto [dt, s] = pq.top();
    pq.pop();

    for (int x : adj[s]) {
      if (ndist[x] > max(dt + 1, a[x])) {
        ndist[x] = max(dt + 1, a[x]);
        pq.emplace(ndist[x], x);
      }
    }
  }

  int ans = INT64_MAX;

  for (int i = 0; i < n; i++) {
    ans = min(ans, max(dist[i], ndist[i]) << 1);
    for (int x : adj[i]) {
      ans = min(ans, max(dist[i], ndist[x]) << 1 | 1);
    }
  }

  cout << ans << '\n';
}

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