oj.uz

Submission #752270

# Submission time Handle Problem Language Result Execution time Memory
752270 2023-06-02T15:47:57 Z tch1cherin Olympic Bus (JOI20_ho_t4) C++17
37 / 100
 955 ms 12764 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 << 2094093 << "\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 42 ms 1108 KB Output is correct
2 Correct 2 ms 468 KB Output is correct
3 Correct 47 ms 1220 KB Output is correct
4 Correct 50 ms 1120 KB Output is correct
5 Correct 3 ms 596 KB Output is correct
6 Correct 6 ms 468 KB Output is correct
7 Correct 0 ms 212 KB Output is correct
8 Correct 1 ms 212 KB Output is correct
9 Correct 1 ms 468 KB Output is correct
10 Correct 57 ms 1204 KB Output is correct
11 Correct 55 ms 1216 KB Output is correct
12 Correct 67 ms 1136 KB Output is correct
13 Correct 17 ms 852 KB Output is correct
14 Correct 31 ms 956 KB Output is correct
15 Correct 32 ms 972 KB Output is correct
16 Correct 40 ms 1052 KB Output is correct

Subtask #2
11.0 / 11.0

# Verdict Execution time Memory Grader output
1 Correct 668 ms 12664 KB Output is correct
2 Correct 636 ms 12748 KB Output is correct
3 Correct 633 ms 12576 KB Output is correct
4 Correct 51 ms 1436 KB Output is correct
5 Correct 30 ms 1100 KB Output is correct
6 Correct 9 ms 596 KB Output is correct
7 Correct 2 ms 468 KB Output is correct
8 Correct 0 ms 212 KB Output is correct
9 Correct 219 ms 12412 KB Output is correct
10 Correct 223 ms 12492 KB Output is correct
11 Correct 412 ms 12416 KB Output is correct
12 Correct 451 ms 12424 KB Output is correct
13 Correct 454 ms 12280 KB Output is correct
14 Correct 403 ms 12764 KB Output is correct

Subtask #3
21.0 / 21.0

# Verdict Execution time Memory Grader output
1 Correct 42 ms 1140 KB Output is correct
2 Correct 8 ms 596 KB Output is correct
3 Correct 270 ms 10024 KB Output is correct
4 Correct 6 ms 468 KB Output is correct
5 Correct 352 ms 12456 KB Output is correct
6 Correct 0 ms 212 KB Output is correct
7 Correct 0 ms 212 KB Output is correct
8 Correct 152 ms 12512 KB Output is correct
9 Correct 156 ms 12420 KB Output is correct
10 Correct 283 ms 12280 KB Output is correct
11 Correct 263 ms 12380 KB Output is correct
12 Correct 245 ms 12660 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 1 ms 212 KB Output is correct
17 Correct 1 ms 212 KB Output is correct
18 Correct 1 ms 212 KB Output is correct
19 Correct 275 ms 12676 KB Output is correct
20 Correct 230 ms 12360 KB Output is correct
21 Correct 291 ms 12388 KB Output is correct
22 Correct 237 ms 12284 KB Output is correct

Subtask #4
0 / 63.0

# Verdict Execution time Memory Grader output
1 Correct 42 ms 1108 KB Output is correct
2 Correct 2 ms 468 KB Output is correct
3 Correct 47 ms 1220 KB Output is correct
4 Correct 50 ms 1120 KB Output is correct
5 Correct 3 ms 596 KB Output is correct
6 Correct 6 ms 468 KB Output is correct
7 Correct 0 ms 212 KB Output is correct
8 Correct 1 ms 212 KB Output is correct
9 Correct 1 ms 468 KB Output is correct
10 Correct 57 ms 1204 KB Output is correct
11 Correct 55 ms 1216 KB Output is correct
12 Correct 67 ms 1136 KB Output is correct
13 Correct 17 ms 852 KB Output is correct
14 Correct 31 ms 956 KB Output is correct
15 Correct 32 ms 972 KB Output is correct
16 Correct 40 ms 1052 KB Output is correct
17 Correct 668 ms 12664 KB Output is correct
18 Correct 636 ms 12748 KB Output is correct
19 Correct 633 ms 12576 KB Output is correct
20 Correct 51 ms 1436 KB Output is correct
21 Correct 30 ms 1100 KB Output is correct
22 Correct 9 ms 596 KB Output is correct
23 Correct 2 ms 468 KB Output is correct
24 Correct 0 ms 212 KB Output is correct
25 Correct 219 ms 12412 KB Output is correct
26 Correct 223 ms 12492 KB Output is correct
27 Correct 412 ms 12416 KB Output is correct
28 Correct 451 ms 12424 KB Output is correct
29 Correct 454 ms 12280 KB Output is correct
30 Correct 403 ms 12764 KB Output is correct
31 Correct 42 ms 1140 KB Output is correct
32 Correct 8 ms 596 KB Output is correct
33 Correct 270 ms 10024 KB Output is correct
34 Correct 6 ms 468 KB Output is correct
35 Correct 352 ms 12456 KB Output is correct
36 Correct 0 ms 212 KB Output is correct
37 Correct 0 ms 212 KB Output is correct
38 Correct 152 ms 12512 KB Output is correct
39 Correct 156 ms 12420 KB Output is correct
40 Correct 283 ms 12280 KB Output is correct
41 Correct 263 ms 12380 KB Output is correct
42 Correct 245 ms 12660 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 1 ms 212 KB Output is correct
47 Correct 1 ms 212 KB Output is correct
48 Correct 1 ms 212 KB Output is correct
49 Correct 275 ms 12676 KB Output is correct
50 Correct 230 ms 12360 KB Output is correct
51 Correct 291 ms 12388 KB Output is correct
52 Correct 237 ms 12284 KB Output is correct
53 Correct 745 ms 12444 KB Output is correct
54 Correct 724 ms 12492 KB Output is correct
55 Correct 718 ms 12720 KB Output is correct
56 Correct 45 ms 1132 KB Output is correct
57 Correct 49 ms 1184 KB Output is correct
58 Correct 556 ms 10116 KB Output is correct
59 Correct 597 ms 10100 KB Output is correct
60 Correct 619 ms 10156 KB Output is correct
61 Correct 572 ms 10028 KB Output is correct
62 Correct 591 ms 10028 KB Output is correct
63 Correct 642 ms 10076 KB Output is correct
64 Correct 955 ms 6248 KB Output is correct
65 Incorrect 954 ms 7164 KB Output isn't correct
66 Halted 0 ms 0 KB -