oj.uz

Submission #1049578

# Submission time Handle Problem Language Result Execution time Memory
1049578 2024-08-09T00:00:20 Z avighna Relay Marathon (NOI20_relaymarathon) C++17
25 / 100
 867 ms 211272 KB 
#include <bits/stdc++.h>

typedef long long ll;

const ll inf = 1e15;

struct Edge {
  ll u, v, w;
};

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

  ll n, m, k;
  std::cin >> n >> m >> k;
  std::vector<std::vector<std::pair<ll, ll>>> adj(n + 1);
  std::vector<Edge> edges;
  for (ll i = 0, u, v, w; i < m; ++i) {
    std::cin >> u >> v >> w;
    adj[u].push_back({v, w});
    adj[v].push_back({u, w});
    edges.push_back({u, v, w});
  }
  std::vector<ll> A(k);
  std::vector<bool> special(n + 1);
  for (auto &i : A) {
    std::cin >> i;
    special[i] = true;
  }

  auto get_best = [&]() {
    std::priority_queue<std::pair<ll, std::pair<ll, ll>>> pq;
    std::vector<ll> d(n + 1, inf);
    for (auto &i : A) {
      pq.push({0, {i, i}});
      d[i] = 0;
    }
    std::vector<std::pair<ll, ll>> closest_special(n + 1);
    std::vector<bool> vis(n + 1);
    while (!pq.empty()) {
      ll node = pq.top().second.first, source = pq.top().second.second,
         dist = -pq.top().first;
      pq.pop();
      if (vis[node]) {
        continue;
      }
      vis[node] = true;
      closest_special[node] = {source, dist};
      for (auto &[i, i_d] : adj[node]) {
        if (dist + i_d < d[i]) {
          d[i] = dist + i_d;
          pq.push({-d[i], {i, source}});
        }
      }
    }

    std::pair<ll, std::pair<ll, ll>> ans = {inf, {0, 0}};
    for (auto &[u, v, w] : edges) {
      if (special[u] and special[v]) {
        ans = std::min(ans, {w, {u, v}});
      }
    }
    for (auto &[u, v, w] : edges) {
      if (closest_special[u].first != closest_special[v].first) {
        ans = std::min(
            ans, {closest_special[u].second + w + closest_special[v].second,
                  {closest_special[u].first, closest_special[v].first}});
      }
    }
    return ans;
  };

  auto sssp = [&](ll x) {
    std::priority_queue<std::pair<ll, ll>> pq;
    pq.push({0, x});
    std::vector<ll> ans(n + 1, inf);
    std::vector<bool> vis(n + 1);
    ans[x] = 0;
    while (!pq.empty()) {
      ll node = pq.top().second, d = -pq.top().first;
      pq.pop();
      if (vis[node]) {
        continue;
      }
      vis[node] = true;
      for (auto &[i, dist] : adj[node]) {
        if (d + dist < ans[i]) {
          ans[i] = d + dist;
          pq.push({-ans[i], i});
        }
      }
    }
    return ans;
  };

  auto best = get_best();
  auto &[u, v] = best.second;
  special[u] = special[v] = false;
  A.erase(std::remove(A.begin(), A.end(), u), A.end());
  A.erase(std::remove(A.begin(), A.end(), v), A.end());
  auto second_best = get_best();
  ll ans = best.first + second_best.first;
  ll f = inf, s = inf;
  auto sssp1 = sssp(u);
  for (ll x = 1; x <= n; ++x) {
    if (x != v and special[x]) {
      f = std::min(f, sssp1[x]);
    }
  }
  auto sssp2 = sssp(v);
  for (ll y = 1; y <= n; ++y) {
    if (y != u and special[y]) {
      s = std::min(s, sssp2[y]);
    }
  }
  if (f != inf and s != inf) {
    ans = std::min(ans, f + s);
  }
  std::cout << ans << '\n';
}

Subtask #1
0 / 5.0

# Verdict Execution time Memory Grader output
1 Incorrect 0 ms 348 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #2
0 / 12.0

# Verdict Execution time Memory Grader output
1 Incorrect 0 ms 348 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #3
25.0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 31 ms 10824 KB Output is correct
2 Correct 4 ms 5724 KB Output is correct
3 Correct 742 ms 211204 KB Output is correct
4 Correct 338 ms 89596 KB Output is correct
5 Correct 86 ms 21752 KB Output is correct
6 Correct 69 ms 17912 KB Output is correct
7 Correct 103 ms 22940 KB Output is correct
8 Correct 35 ms 11016 KB Output is correct
9 Correct 64 ms 15872 KB Output is correct
10 Correct 51 ms 12552 KB Output is correct
11 Correct 789 ms 211272 KB Output is correct
12 Correct 50 ms 13320 KB Output is correct
13 Correct 222 ms 54148 KB Output is correct
14 Correct 98 ms 23468 KB Output is correct
15 Correct 789 ms 209612 KB Output is correct
16 Correct 25 ms 9996 KB Output is correct
17 Correct 529 ms 139736 KB Output is correct
18 Correct 4 ms 5784 KB Output is correct
19 Correct 867 ms 209876 KB Output is correct
20 Correct 104 ms 22272 KB Output is correct
21 Correct 91 ms 19448 KB Output is correct
22 Correct 47 ms 13068 KB Output is correct
23 Correct 13 ms 8464 KB Output is correct
24 Correct 573 ms 147744 KB Output is correct
25 Correct 65 ms 15876 KB Output is correct
26 Correct 35 ms 11016 KB Output is correct
27 Correct 53 ms 13964 KB Output is correct
28 Correct 8 ms 7140 KB Output is correct
29 Correct 98 ms 22008 KB Output is correct
30 Correct 196 ms 43760 KB Output is correct

Subtask #4
0 / 58.0

# Verdict Execution time Memory Grader output
1 Incorrect 0 ms 348 KB Output isn't correct
2 Halted 0 ms 0 KB -