oj.uz

Submission #752245

# Submission time Handle Problem Language Result Execution time Memory
752245 2023-06-02T15:11:27 Z tch1cherin Olympic Bus (JOI20_ho_t4) C++17
37 / 100
 753 ms 25296 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) {
      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);
  assert(1.0 * clock() / CLOCKS_PER_SEC <= 0.7);
  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:79:12: warning: variable 'flag' set but not used [-Wunused-but-set-variable]
   79 |       bool flag = true;
      |            ^~~~

Subtask #1
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 40 ms 1100 KB Output is correct
2 Correct 3 ms 468 KB Output is correct
3 Correct 45 ms 1140 KB Output is correct
4 Correct 47 ms 1228 KB Output is correct
5 Correct 3 ms 596 KB Output is correct
6 Correct 5 ms 468 KB Output is correct
7 Correct 0 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 67 ms 1216 KB Output is correct
11 Correct 57 ms 1204 KB Output is correct
12 Correct 53 ms 1216 KB Output is correct
13 Correct 16 ms 852 KB Output is correct
14 Correct 31 ms 1028 KB Output is correct
15 Correct 29 ms 1072 KB Output is correct
16 Correct 32 ms 1048 KB Output is correct

Subtask #2
11.0 / 11.0

# Verdict Execution time Memory Grader output
1 Correct 626 ms 12628 KB Output is correct
2 Correct 629 ms 12608 KB Output is correct
3 Correct 626 ms 12756 KB Output is correct
4 Correct 45 ms 1452 KB Output is correct
5 Correct 27 ms 1108 KB Output is correct
6 Correct 8 ms 688 KB Output is correct
7 Correct 2 ms 468 KB Output is correct
8 Correct 0 ms 212 KB Output is correct
9 Correct 196 ms 12572 KB Output is correct
10 Correct 197 ms 12480 KB Output is correct
11 Correct 422 ms 12392 KB Output is correct
12 Correct 441 ms 12372 KB Output is correct
13 Correct 407 ms 12436 KB Output is correct
14 Correct 403 ms 13040 KB Output is correct

Subtask #3
21.0 / 21.0

# Verdict Execution time Memory Grader output
1 Correct 38 ms 1108 KB Output is correct
2 Correct 8 ms 532 KB Output is correct
3 Correct 288 ms 9948 KB Output is correct
4 Correct 6 ms 580 KB Output is correct
5 Correct 331 ms 12660 KB Output is correct
6 Correct 1 ms 212 KB Output is correct
7 Correct 1 ms 212 KB Output is correct
8 Correct 153 ms 12468 KB Output is correct
9 Correct 153 ms 12496 KB Output is correct
10 Correct 262 ms 12416 KB Output is correct
11 Correct 243 ms 12296 KB Output is correct
12 Correct 232 ms 12588 KB Output is correct
13 Correct 0 ms 212 KB Output is correct
14 Correct 0 ms 212 KB Output is correct
15 Correct 1 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 0 ms 212 KB Output is correct
19 Correct 283 ms 12620 KB Output is correct
20 Correct 240 ms 12368 KB Output is correct
21 Correct 224 ms 12460 KB Output is correct
22 Correct 240 ms 12396 KB Output is correct

Subtask #4
0 / 63.0

# Verdict Execution time Memory Grader output
1 Correct 40 ms 1100 KB Output is correct
2 Correct 3 ms 468 KB Output is correct
3 Correct 45 ms 1140 KB Output is correct
4 Correct 47 ms 1228 KB Output is correct
5 Correct 3 ms 596 KB Output is correct
6 Correct 5 ms 468 KB Output is correct
7 Correct 0 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 67 ms 1216 KB Output is correct
11 Correct 57 ms 1204 KB Output is correct
12 Correct 53 ms 1216 KB Output is correct
13 Correct 16 ms 852 KB Output is correct
14 Correct 31 ms 1028 KB Output is correct
15 Correct 29 ms 1072 KB Output is correct
16 Correct 32 ms 1048 KB Output is correct
17 Correct 626 ms 12628 KB Output is correct
18 Correct 629 ms 12608 KB Output is correct
19 Correct 626 ms 12756 KB Output is correct
20 Correct 45 ms 1452 KB Output is correct
21 Correct 27 ms 1108 KB Output is correct
22 Correct 8 ms 688 KB Output is correct
23 Correct 2 ms 468 KB Output is correct
24 Correct 0 ms 212 KB Output is correct
25 Correct 196 ms 12572 KB Output is correct
26 Correct 197 ms 12480 KB Output is correct
27 Correct 422 ms 12392 KB Output is correct
28 Correct 441 ms 12372 KB Output is correct
29 Correct 407 ms 12436 KB Output is correct
30 Correct 403 ms 13040 KB Output is correct
31 Correct 38 ms 1108 KB Output is correct
32 Correct 8 ms 532 KB Output is correct
33 Correct 288 ms 9948 KB Output is correct
34 Correct 6 ms 580 KB Output is correct
35 Correct 331 ms 12660 KB Output is correct
36 Correct 1 ms 212 KB Output is correct
37 Correct 1 ms 212 KB Output is correct
38 Correct 153 ms 12468 KB Output is correct
39 Correct 153 ms 12496 KB Output is correct
40 Correct 262 ms 12416 KB Output is correct
41 Correct 243 ms 12296 KB Output is correct
42 Correct 232 ms 12588 KB Output is correct
43 Correct 0 ms 212 KB Output is correct
44 Correct 0 ms 212 KB Output is correct
45 Correct 1 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 0 ms 212 KB Output is correct
49 Correct 283 ms 12620 KB Output is correct
50 Correct 240 ms 12368 KB Output is correct
51 Correct 224 ms 12460 KB Output is correct
52 Correct 240 ms 12396 KB Output is correct
53 Runtime error 753 ms 25296 KB Execution killed with signal 6
54 Halted 0 ms 0 KB -