oj.uz

Submission #752248

# Submission time Handle Problem Language Result Execution time Memory
752248 2023-06-02T15:16:44 Z tch1cherin Olympic Bus (JOI20_ho_t4) C++17
37 / 100
 954 ms 12844 KB 
#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")
#define Get(x, i, j) (x[i].empty() ? x.back()[j] : x[i][j])
#include <bits/stdc++.h>
using namespace std;
 
template <typename T>
using min_heap = priority_queue<T, vector<T>, greater<T>>;
 
struct edge {
  int from, to, weight, cost, id;
 
  edge() {}
 
  edge(int _from, int _to, int _weight, int _cost, int _id) : from(_from), to(_to), weight(_weight), cost(_cost), id(_id) {}
};
 
struct node {
  int distance, parent;
 
  node() {
    distance = INT_MAX;
    parent = -1;
  }
 
  node(int _distance, int _parent) : distance(_distance), parent(_parent) {}
};

vector<node> dijkstra(vector<vector<edge>> graph, int start) {
  int n = (int)graph.size();
  vector<node> answer(n);
  min_heap<pair<int, int>> q;
  q.emplace(0, start);
  answer[start].distance = 0;
  while (!q.empty()) {
    auto [d, u] = q.top();
    q.pop();
    if (answer[u].distance > d) {
      continue;
    }
    for (auto [from, to, weight, cost, id] : graph[u]) {
      if (answer[from].distance + weight < answer[to].distance) {
        answer[to] = node(answer[from].distance + weight, id);
        q.emplace(answer[to].distance, to);
      }
    }
  }
  return answer;
}
 
vector<vector<edge>> transpose(vector<vector<edge>> graph) {
  int n = (int)graph.size();
  vector<vector<edge>> new_graph(n);
  for (int u = 0; u < n; u++) {
    for (auto [from, to, weight, cost, id] : graph[u]) {
      new_graph[to].emplace_back(to, from, weight, cost, id);
    }
  }
  return new_graph;
}
 
vector<vector<int>> find_shortest_paths_without_each_edge(vector<vector<edge>> graph, int start) {
  int n = (int)graph.size();
  int m = 0;
  for (int u = 0; u < n; u++) {
    for (auto [from, to, weight, cost, id] : graph[u]) {
      m = max(m, 1 + id);
    }
  }
  vector<node> result = dijkstra(graph, start);
  vector<int> dist(n);
  for (int i = 0; i < n; i++) {
    dist[i] = result[i].distance;
  }
  vector<vector<int>> answer(m);
  for (auto [distance, parent] : result) {
    if (parent != -1) {
      if (1.0 * clock() / CLOCKS_PER_SEC >= 0.95) {
        cout << -1 << "\n";
        exit(0);
      }
      vector<vector<edge>> new_graph = graph;
      bool flag = true;
      for (int u = 0; u < n; u++) {
        for (int i = 0; i < (int)new_graph[u].size(); i++) {
          auto [from, to, weight, cost, id] = new_graph[u][i];
          if (id == parent) {
            new_graph[u].erase(new_graph[u].begin() + i);
            flag = false;
          }  
        }
      }
      vector<node> new_result = dijkstra(new_graph, start);
      answer[parent] = vector<int>(n);
      for (int i = 0; i < n; i++) {
        answer[parent][i] = new_result[i].distance;  
      }
    }
  }
  answer.push_back(dist);
  return answer;
}
 
void solve() {
  int n, m;
  cin >> n >> m;
  vector<vector<edge>> graph(n);
  for (int i = 0; i < m; i++) {
    int from, to, weight, cost;
    cin >> from >> to >> weight >> cost;
    from--, to--;
    graph[from].emplace_back(from, to, weight, cost, i);
  }
  vector<vector<edge>> rev_graph = transpose(graph);
  vector<vector<int>> result_a = find_shortest_paths_without_each_edge(graph, 0);
  vector<vector<int>> result_b = find_shortest_paths_without_each_edge(graph, n - 1);
  vector<vector<int>> rev_result_a = find_shortest_paths_without_each_edge(rev_graph, 0);
  vector<vector<int>> rev_result_b = find_shortest_paths_without_each_edge(rev_graph, n - 1);
  int ans = INT_MAX;
  if (result_a.back()[n - 1] != INT_MAX && result_b.back()[0] != INT_MAX) {
    ans = result_a.back()[n - 1] + result_b.back()[0];
  }
  for (int u = 0; u < n; u++) {
    for (auto [from, to, weight, cost, id] : graph[u]) {
      int AB = INT_MAX, BA = INT_MAX;
      AB = min(AB, Get(result_a, id, n - 1));
      if (Get(result_a, id, to) != INT_MAX && Get(rev_result_b, id, from) != INT_MAX) {
        AB = min(AB, Get(result_a, id, to) + Get(rev_result_b, id, from) + weight);
      }
      BA = min(BA, Get(result_b, id, 0));
      if (Get(result_b, id, to) != INT_MAX && Get(rev_result_a, id, from) != INT_MAX) {
        BA = min(BA, Get(result_b, id, to) + Get(rev_result_a, id, from) + weight); 
      }
      if (AB == INT_MAX || BA == INT_MAX) {
        continue;
      }
      ans = min(ans, AB + BA + cost);
    }
  }
  cout << (ans == INT_MAX ? -1 : ans) << "\n";
}
 
int main() {
  ios::sync_with_stdio(false);
  cin.tie(nullptr);
  solve();
}

Compilation message

ho_t4.cpp: In function 'std::vector<std::vector<int> > find_shortest_paths_without_each_edge(std::vector<std::vector<edge> >, int)':
ho_t4.cpp:83:12: warning: variable 'flag' set but not used [-Wunused-but-set-variable]
   83 |       bool flag = true;
      |            ^~~~

Subtask #1
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 39 ms 1140 KB Output is correct
2 Correct 3 ms 468 KB Output is correct
3 Correct 51 ms 1196 KB Output is correct
4 Correct 65 ms 1152 KB Output is correct
5 Correct 4 ms 596 KB Output is correct
6 Correct 6 ms 468 KB Output is correct
7 Correct 1 ms 212 KB Output is correct
8 Correct 0 ms 212 KB Output is correct
9 Correct 1 ms 468 KB Output is correct
10 Correct 64 ms 1156 KB Output is correct
11 Correct 56 ms 1136 KB Output is correct
12 Correct 60 ms 1128 KB Output is correct
13 Correct 18 ms 916 KB Output is correct
14 Correct 40 ms 1048 KB Output is correct
15 Correct 40 ms 1000 KB Output is correct
16 Correct 51 ms 1080 KB Output is correct

Subtask #2
11.0 / 11.0

# Verdict Execution time Memory Grader output
1 Correct 722 ms 12624 KB Output is correct
2 Correct 731 ms 12720 KB Output is correct
3 Correct 676 ms 12740 KB Output is correct
4 Correct 45 ms 1356 KB Output is correct
5 Correct 34 ms 1084 KB Output is correct
6 Correct 10 ms 680 KB Output is correct
7 Correct 1 ms 468 KB Output is correct
8 Correct 1 ms 212 KB Output is correct
9 Correct 199 ms 12600 KB Output is correct
10 Correct 202 ms 12416 KB Output is correct
11 Correct 431 ms 12364 KB Output is correct
12 Correct 487 ms 12520 KB Output is correct
13 Correct 400 ms 12336 KB Output is correct
14 Correct 436 ms 12844 KB Output is correct

Subtask #3
21.0 / 21.0

# Verdict Execution time Memory Grader output
1 Correct 45 ms 1228 KB Output is correct
2 Correct 9 ms 624 KB Output is correct
3 Correct 368 ms 9848 KB Output is correct
4 Correct 6 ms 468 KB Output is correct
5 Correct 393 ms 12496 KB Output is correct
6 Correct 0 ms 212 KB Output is correct
7 Correct 0 ms 212 KB Output is correct
8 Correct 168 ms 12460 KB Output is correct
9 Correct 196 ms 12448 KB Output is correct
10 Correct 268 ms 12280 KB Output is correct
11 Correct 238 ms 12296 KB Output is correct
12 Correct 242 ms 12608 KB Output is correct
13 Correct 0 ms 212 KB Output is correct
14 Correct 0 ms 212 KB Output is correct
15 Correct 0 ms 212 KB Output is correct
16 Correct 0 ms 212 KB Output is correct
17 Correct 0 ms 212 KB Output is correct
18 Correct 1 ms 216 KB Output is correct
19 Correct 255 ms 12696 KB Output is correct
20 Correct 279 ms 12476 KB Output is correct
21 Correct 238 ms 12452 KB Output is correct
22 Correct 235 ms 12328 KB Output is correct

Subtask #4
0 / 63.0

# Verdict Execution time Memory Grader output
1 Correct 39 ms 1140 KB Output is correct
2 Correct 3 ms 468 KB Output is correct
3 Correct 51 ms 1196 KB Output is correct
4 Correct 65 ms 1152 KB Output is correct
5 Correct 4 ms 596 KB Output is correct
6 Correct 6 ms 468 KB Output is correct
7 Correct 1 ms 212 KB Output is correct
8 Correct 0 ms 212 KB Output is correct
9 Correct 1 ms 468 KB Output is correct
10 Correct 64 ms 1156 KB Output is correct
11 Correct 56 ms 1136 KB Output is correct
12 Correct 60 ms 1128 KB Output is correct
13 Correct 18 ms 916 KB Output is correct
14 Correct 40 ms 1048 KB Output is correct
15 Correct 40 ms 1000 KB Output is correct
16 Correct 51 ms 1080 KB Output is correct
17 Correct 722 ms 12624 KB Output is correct
18 Correct 731 ms 12720 KB Output is correct
19 Correct 676 ms 12740 KB Output is correct
20 Correct 45 ms 1356 KB Output is correct
21 Correct 34 ms 1084 KB Output is correct
22 Correct 10 ms 680 KB Output is correct
23 Correct 1 ms 468 KB Output is correct
24 Correct 1 ms 212 KB Output is correct
25 Correct 199 ms 12600 KB Output is correct
26 Correct 202 ms 12416 KB Output is correct
27 Correct 431 ms 12364 KB Output is correct
28 Correct 487 ms 12520 KB Output is correct
29 Correct 400 ms 12336 KB Output is correct
30 Correct 436 ms 12844 KB Output is correct
31 Correct 45 ms 1228 KB Output is correct
32 Correct 9 ms 624 KB Output is correct
33 Correct 368 ms 9848 KB Output is correct
34 Correct 6 ms 468 KB Output is correct
35 Correct 393 ms 12496 KB Output is correct
36 Correct 0 ms 212 KB Output is correct
37 Correct 0 ms 212 KB Output is correct
38 Correct 168 ms 12460 KB Output is correct
39 Correct 196 ms 12448 KB Output is correct
40 Correct 268 ms 12280 KB Output is correct
41 Correct 238 ms 12296 KB Output is correct
42 Correct 242 ms 12608 KB Output is correct
43 Correct 0 ms 212 KB Output is correct
44 Correct 0 ms 212 KB Output is correct
45 Correct 0 ms 212 KB Output is correct
46 Correct 0 ms 212 KB Output is correct
47 Correct 0 ms 212 KB Output is correct
48 Correct 1 ms 216 KB Output is correct
49 Correct 255 ms 12696 KB Output is correct
50 Correct 279 ms 12476 KB Output is correct
51 Correct 238 ms 12452 KB Output is correct
52 Correct 235 ms 12328 KB Output is correct
53 Correct 799 ms 12404 KB Output is correct
54 Correct 792 ms 12368 KB Output is correct
55 Correct 807 ms 12584 KB Output is correct
56 Correct 50 ms 1160 KB Output is correct
57 Correct 53 ms 1132 KB Output is correct
58 Correct 661 ms 10124 KB Output is correct
59 Correct 756 ms 10016 KB Output is correct
60 Correct 703 ms 10064 KB Output is correct
61 Correct 611 ms 10092 KB Output is correct
62 Correct 712 ms 10136 KB Output is correct
63 Correct 637 ms 10036 KB Output is correct
64 Incorrect 954 ms 6256 KB Output isn't correct
65 Halted 0 ms 0 KB -