Submission #897678

#	Time	Username	Problem	Language	Result	Execution time	Memory
897678		avighna	Olympic Bus (JOI20_ho_t4)	C++17	5 / 100	1096 ms	4476 KiB

ho_t4

#include <bits/stdc++.h>

using namespace std;

#define ll long long

const ll N = 201, M = 50001;

ll n, m;

vector<pair<ll, ll>> adj[N];
ll c[M], d[M];
pair<ll, ll> edges[M];

vector<ll> sssp(ll source, ll i, bool b) {
  vector<ll> dist(n + 1, 1e15);
  dist[source] = 0;
  priority_queue<pair<ll, ll>> pq;
  pq.push({0, source});
  while (!pq.empty()) {
    ll node = pq.top().second, _dist = -pq.top().first;
    pq.pop();
    for (auto &nb : adj[node]) {
      if (edges[nb.second].first != node) {
        if (!(nb.second == i && b)) {
          continue;
        }
      } else if (nb.second == i and b) {
        continue;
      }
      if (dist[nb.first] > _dist + c[nb.second]) {
        dist[nb.first] = _dist + c[nb.second];
        pq.push({-dist[nb.first], nb.first});
      }
    }
  }
  return dist;
}

int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);

  cin >> n >> m;
  for (ll i = 1; i <= n; ++i) {
    adj[i].clear();
  }
  for (ll i = 0, u, v; i < m; ++i) {
    cin >> u >> v >> c[i] >> d[i];
    adj[u].emplace_back(v, i), adj[v].emplace_back(u, i);
    edges[i] = {u, v};
  }

  ll ans = min((ll)1e15, sssp(1, 0, 0)[n] + sssp(n, 0, 0)[1]);
  for (ll i = 0; i < m; ++i) {
    ans = min(ans, d[i] + sssp(1, i, 1)[n] + sssp(n, i, 1)[1]);
  }
  if (ans == (ll)1e15) {
    ans = -1;
  }
  cout << ans << "\n";
}

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