Submission #1167569

#	Time	Username	Problem	Language	Result	Execution time	Memory
1167569		kunzaZa183	Olympic Bus (JOI20_ho_t4)	C++20	5 / 100	1095 ms	7120 KiB

ho_t4

#include <bits/stdc++.h>
using namespace std;
#define int long long
signed main() {
  cin.tie(0)->sync_with_stdio(0);

  int n, m;
  cin >> n >> m;

  vector<vector<int>> elist;
  elist.push_back({0, 0, 0, 0});

  for (int i = 0; i < m; i++) {
    int a, b, c, d;
    cin >> a >> b >> c >> d;
    a--, b--;
    elist.push_back({a, b, c, d});
  }

  int minans = INT_MAX;
  for (int i = 0; i <= m; i++) {
    vector<vector<pair<int, int>>> adj(n, vector<pair<int, int>>());

    int curp = elist[i][3];

    swap(elist[i][0], elist[i][1]);

    // cout << "ELIST\n";
    // for (auto a : elist) {
    //   for (auto b : a) cout << b << " ";
    //   cout << "\n";
    // }

    for (int j = 0; j <= m; j++) {
      adj[elist[j][0]].emplace_back(elist[j][1], elist[j][2]);
    }

    vector<int> visited(n, INT_MAX);

    priority_queue<pair<int, int>, vector<pair<int, int>>,
                   greater<pair<int, int>>>
        pqpii;
    pqpii.emplace(0, 0);

    while (!pqpii.empty()) {
      pair<int, int> cur = pqpii.top();
      pqpii.pop();

      if (visited[cur.second] != INT_MAX) continue;

      visited[cur.second] = cur.first;

      for (auto a : adj[cur.second])
        pqpii.emplace(a.second + cur.first, a.first);
    }

    curp += visited[n - 1];

    // cout<<curp<<"\n";

    pqpii.emplace(0, n - 1);
    visited = vector<int>(n, INT_MAX);

    while (!pqpii.empty()) {
      pair<int, int> cur = pqpii.top();
      pqpii.pop();

      // cout<<cur.first<<" "<<cur.second<<"\n";

      if (visited[cur.second] != INT_MAX) continue;

      visited[cur.second] = cur.first;

      for (auto a : adj[cur.second])
        pqpii.emplace(a.second + cur.first, a.first);
    }

    curp += visited[0];

    // cout<<curp<<"\n";

    minans = min(minans, curp);

    swap(elist[i][0], elist[i][1]);
  }

  if (minans == INT_MAX)
    cout << "-1\n";
  else
    cout << minans << "\n";
}

• Subtask 1: 5 / 5
• Subtask 2: 0 / 11
• Subtask 3: 0 / 21
• Subtask 4: 0 / 63