oj.uz

답안 #1080968

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
1080968 2024-08-29T16:28:23 Z avighna Aesthetic (NOI20_aesthetic) C++17
20 / 100
 2000 ms 39508 KB 
#include <bits/stdc++.h>

typedef long long ll;

struct To {
  ll v, w;
  ll i;
};

const ll inf = 1e15;

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

  ll n, m;
  std::cin >> n >> m;
  std::vector<std::vector<To>> adj(n + 1);
  std::vector<ll> roads(m);
  for (ll i = 0, u, v, w; i < m; ++i) {
    std::cin >> u >> v >> w;
    adj[u].push_back({v, w, i});
    adj[v].push_back({u, w, i});
    roads[i] = w;
  }

  if (m == n - 1) {
    // there will only be one path
    std::set<ll> edges;
    std::function<bool(ll, ll)> dfs;
    ll def = 0;
    dfs = [&](ll node, ll par) {
      if (node == n) {
        return true;
      }
      for (auto &[ch, w, i] : adj[node]) {
        if (ch == par) {
          continue;
        }
        if (dfs(ch, node)) {
          edges.insert(i);
          def += w;
          return true;
        }
      }
      return false;
    };
    dfs(1, 0);

    ll ans = def;
    ll worst_road = roads[m - 1];
    for (ll i = m - 2; i >= 0; --i) {
      if (edges.count(i)) {
        ans = std::max(ans, def + worst_road);
      }
      worst_road = std::max(worst_road, roads[i]);
    }
    std::cout << ans << '\n';

    return 0;
  }

  // exclude edge i
  auto sssp = [&](ll i, ll add) {
    std::vector<ll> ans(n + 1, inf);
    std::vector<bool> vis(n + 1);
    std::priority_queue<std::pair<ll, ll>> pq;
    pq.push({0, 1});
    while (!pq.empty()) {
      auto [d, node] = pq.top();
      d *= -1;
      pq.pop();
      if (vis[node]) {
        continue;
      }
      vis[node] = true;
      for (auto [ch, w, cur_i] : adj[node]) {
        if (cur_i == i) {
          w += add;
        }
        if (ans[ch] > d + w) {
          ans[ch] = d + w;
          pq.push({-ans[ch], ch});
        }
      }
    }
    return ans;
  };

  ll def = sssp(-1, 0)[n];
  ll ans = def;
  ll worst_road = roads[m - 1];
  for (ll i = m - 2; i >= 0; --i) {
    ans = std::max(ans, sssp(i, worst_road)[n]);
    worst_road = std::max(worst_road, roads[i]);
  }
  std::cout << ans << '\n';
}

Subtask #1
5.0 / 5.0

# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 344 KB Output is correct
2 Correct 1 ms 600 KB Output is correct
3 Correct 1 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 0 ms 348 KB Output is correct
6 Correct 1 ms 348 KB Output is correct
7 Correct 1 ms 456 KB Output is correct
8 Correct 1 ms 348 KB Output is correct

Subtask #2
8.0 / 8.0

# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 344 KB Output is correct
2 Correct 1 ms 600 KB Output is correct
3 Correct 1 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 0 ms 348 KB Output is correct
6 Correct 1 ms 348 KB Output is correct
7 Correct 1 ms 456 KB Output is correct
8 Correct 1 ms 348 KB Output is correct
9 Correct 218 ms 696 KB Output is correct
10 Correct 200 ms 604 KB Output is correct
11 Correct 135 ms 604 KB Output is correct
12 Correct 143 ms 604 KB Output is correct
13 Correct 68 ms 600 KB Output is correct
14 Correct 66 ms 604 KB Output is correct
15 Correct 82 ms 704 KB Output is correct
16 Correct 66 ms 604 KB Output is correct

Subtask #3
7.0 / 7.0

# 결과 실행 시간 메모리 Grader output
1 Correct 140 ms 36664 KB Output is correct
2 Correct 163 ms 37200 KB Output is correct
3 Correct 135 ms 36616 KB Output is correct
4 Correct 149 ms 36508 KB Output is correct
5 Correct 151 ms 36688 KB Output is correct
6 Correct 169 ms 37476 KB Output is correct
7 Correct 185 ms 37440 KB Output is correct
8 Correct 138 ms 37456 KB Output is correct

Subtask #4
0 / 15.0

# 결과 실행 시간 메모리 Grader output
1 Execution timed out 2098 ms 39508 KB Time limit exceeded
2 Halted 0 ms 0 KB -

Subtask #5
0 / 16.0

# 결과 실행 시간 메모리 Grader output
1 Execution timed out 2019 ms 37152 KB Time limit exceeded
2 Halted 0 ms 0 KB -

Subtask #6
0 / 22.0

# 결과 실행 시간 메모리 Grader output
1 Execution timed out 2019 ms 37152 KB Time limit exceeded
2 Halted 0 ms 0 KB -

Subtask #7
0 / 27.0

# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 344 KB Output is correct
2 Correct 1 ms 600 KB Output is correct
3 Correct 1 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 0 ms 348 KB Output is correct
6 Correct 1 ms 348 KB Output is correct
7 Correct 1 ms 456 KB Output is correct
8 Correct 1 ms 348 KB Output is correct
9 Correct 218 ms 696 KB Output is correct
10 Correct 200 ms 604 KB Output is correct
11 Correct 135 ms 604 KB Output is correct
12 Correct 143 ms 604 KB Output is correct
13 Correct 68 ms 600 KB Output is correct
14 Correct 66 ms 604 KB Output is correct
15 Correct 82 ms 704 KB Output is correct
16 Correct 66 ms 604 KB Output is correct
17 Correct 140 ms 36664 KB Output is correct
18 Correct 163 ms 37200 KB Output is correct
19 Correct 135 ms 36616 KB Output is correct
20 Correct 149 ms 36508 KB Output is correct
21 Correct 151 ms 36688 KB Output is correct
22 Correct 169 ms 37476 KB Output is correct
23 Correct 185 ms 37440 KB Output is correct
24 Correct 138 ms 37456 KB Output is correct
25 Execution timed out 2098 ms 39508 KB Time limit exceeded
26 Halted 0 ms 0 KB -