oj.uz

Submission #1049855

# Submission time Handle Problem Language Result Execution time Memory
1049855 2024-08-09T05:47:00 Z avighna Relay Marathon (NOI20_relaymarathon) C++17
25 / 100
 918 ms 211028 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;
  auto sssp1 = sssp(u);
  std::vector<std::pair<ll, ll>> best1;
  for (ll x = 1; x <= n; ++x) {
    if (x != v and special[x]) {
      best1.push_back({sssp1[x], x});
    }
  }
  auto sssp2 = sssp(v);
  std::vector<std::pair<ll, ll>> best2;
  for (ll y = 1; y <= n; ++y) {
    if (y != u and special[y]) {
      best2.push_back({sssp1[y], y});
    }
  }
  std::sort(best1.begin(), best1.end());
  std::sort(best2.begin(), best2.end());
  if (!best1.empty() and !best2.empty()) {
    if (best1[0].second != best2[0].second) {
      ans = std::min(ans, best1[0].first + best2[0].first);
    } else {
      if (best2.size() >= 2) {
        ans = std::min(ans, best1[0].first + best2[1].first);
      }
      if (best1.size() >= 2) {
        ans = std::min(ans, best1[1].first + best2[0].first);
      }
    }
  }
  std::cout << ans << '\n';
}

Subtask #1
0 / 5.0

# Verdict Execution time Memory Grader output
1 Incorrect 1 ms 344 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #2
0 / 12.0

# Verdict Execution time Memory Grader output
1 Incorrect 1 ms 344 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 33 ms 10764 KB Output is correct
2 Correct 5 ms 5724 KB Output is correct
3 Correct 893 ms 210136 KB Output is correct
4 Correct 484 ms 88104 KB Output is correct
5 Correct 148 ms 20892 KB Output is correct
6 Correct 117 ms 18432 KB Output is correct
7 Correct 142 ms 23508 KB Output is correct
8 Correct 42 ms 12096 KB Output is correct
9 Correct 69 ms 15580 KB Output is correct
10 Correct 47 ms 12556 KB Output is correct
11 Correct 918 ms 209356 KB Output is correct
12 Correct 55 ms 13312 KB Output is correct
13 Correct 225 ms 56012 KB Output is correct
14 Correct 101 ms 22968 KB Output is correct
15 Correct 809 ms 211028 KB Output is correct
16 Correct 26 ms 9988 KB Output is correct
17 Correct 561 ms 139544 KB Output is correct
18 Correct 6 ms 5780 KB Output is correct
19 Correct 855 ms 209936 KB Output is correct
20 Correct 96 ms 21504 KB Output is correct
21 Correct 86 ms 21240 KB Output is correct
22 Correct 42 ms 12812 KB Output is correct
23 Correct 13 ms 8492 KB Output is correct
24 Correct 541 ms 148052 KB Output is correct
25 Correct 74 ms 15708 KB Output is correct
26 Correct 36 ms 10944 KB Output is correct
27 Correct 52 ms 14124 KB Output is correct
28 Correct 10 ms 7144 KB Output is correct
29 Correct 94 ms 22852 KB Output is correct
30 Correct 190 ms 43524 KB Output is correct

Subtask #4
0 / 58.0

# Verdict Execution time Memory Grader output
1 Incorrect 1 ms 344 KB Output isn't correct
2 Halted 0 ms 0 KB -