oj.uz

Submission #752238

# Submission time Handle Problem Language Result Execution time Memory
752238 2023-06-02T14:43:54 Z tch1cherin Olympic Bus (JOI20_ho_t4) C++17
37 / 100
 1000 ms 83408 KB 
#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")
#include <bits/stdc++.h>
using namespace std;

// Trash code from https://www.geeksforgeeks.org/pairing-heap/
struct HeapNode {
    pair<int, int> key;
    HeapNode *leftChild;
    HeapNode *nextSibling;
 
    HeapNode():
        leftChild(NULL), nextSibling(NULL) {}
 
    // creates a new node
    HeapNode(pair<int, int> key_, HeapNode *leftChild_, HeapNode *nextSibling_):
        key(key_), leftChild(leftChild_), nextSibling(nextSibling_) {}
         
        // Adds a child and sibling to the node
    void addChild(HeapNode *node) {
        if(leftChild == NULL)
            leftChild = node;
        else {
            node->nextSibling = leftChild;
            leftChild = node;
        }
    }
};
 
// Returns true if root of the tree
// is null otherwise returns false
bool Empty(HeapNode *node) {
    return (node == NULL);
}
 
// Function to merge two heaps
HeapNode *Merge(HeapNode *A, HeapNode *B)
{
    // If any of the two-nodes is null
    // the return the not null node
    if(A == NULL) return B;
    if(B == NULL) return A;
     
    // To maintain the min heap condition compare   
    // the nodes and node with minimum value become 
    // parent of the other node
    if(A->key < B->key) {                 
        A->addChild(B);
        return A;        
    }
    else {
        B->addChild(A);
        return B;
    }
 
    return NULL; // Unreachable
}
 
// Returns the root value of the heap
pair<int, int> Top(HeapNode *node) {
    return node->key;
}
 
// Function to insert the new node in the heap
HeapNode *Insert(HeapNode *node, pair<int, int> key) {
    return Merge(node, new HeapNode(key, NULL, NULL));
}
 
// This method is used when we want to delete root node
HeapNode *TwoPassMerge(HeapNode *node) {
    if(node == NULL || node->nextSibling == NULL)
        return node;
    else {
        HeapNode *A, *B, *newNode;
        A = node;
        B = node->nextSibling;
        newNode = node->nextSibling->nextSibling;
 
        A->nextSibling = NULL;
        B->nextSibling = NULL;
 
        return Merge(Merge(A, B), TwoPassMerge(newNode));
    }
 
    return NULL; // Unreachable
}
 
// Function to delete the root node in heap
HeapNode *Delete(HeapNode *node) {
    return TwoPassMerge(node->leftChild);
}
 
struct PairingHeap {
    HeapNode *root;
 
    PairingHeap():
        root(NULL) {}
 
    bool Empty(void) {
        return ::Empty(root);
    }
 
    pair<int, int> Top(void) {
        return ::Top(root);
    }
 
    void Insert(pair<int, int> key) {
        root = ::Insert(root, key);
    }
 
    void Delete(void) {
        root = ::Delete(root);
    }
 
    void Join(PairingHeap other) {
        root = ::Merge(root, other.root);
    }
     
};

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) {}
};

struct result {
  int edge;
  vector<int> distances; 
};

vector<node> dijkstra(vector<vector<edge>> graph, int start) {
  int n = (int)graph.size();
  vector<node> answer(n);
  PairingHeap q;
  q.Insert({0, start});
  answer[start].distance = 0;
  while (!q.Empty()) {
    auto [d, u] = q.Top();
    q.Delete();
    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.Insert({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;
      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);
            break;
          }  
        }
      }
      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);
  auto get = [](vector<vector<int>>& x, int i, int j) {
    if (x[i].empty()) {
      return x.back()[j];
    } else {
      return x[i][j];
    }
  };
  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();
}

Subtask #1
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 42 ms 6092 KB Output is correct
2 Correct 3 ms 596 KB Output is correct
3 Correct 57 ms 8244 KB Output is correct
4 Correct 60 ms 8596 KB Output is correct
5 Correct 4 ms 980 KB Output is correct
6 Correct 6 ms 852 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 65 ms 11228 KB Output is correct
11 Correct 63 ms 11148 KB Output is correct
12 Correct 66 ms 11036 KB Output is correct
13 Correct 18 ms 2276 KB Output is correct
14 Correct 39 ms 5620 KB Output is correct
15 Correct 35 ms 5320 KB Output is correct
16 Correct 40 ms 5576 KB Output is correct

Subtask #2
11.0 / 11.0

# Verdict Execution time Memory Grader output
1 Correct 557 ms 34988 KB Output is correct
2 Correct 563 ms 34244 KB Output is correct
3 Correct 591 ms 34880 KB Output is correct
4 Correct 51 ms 8612 KB Output is correct
5 Correct 36 ms 5600 KB Output is correct
6 Correct 10 ms 1748 KB Output is correct
7 Correct 2 ms 468 KB Output is correct
8 Correct 0 ms 212 KB Output is correct
9 Correct 174 ms 17468 KB Output is correct
10 Correct 176 ms 17428 KB Output is correct
11 Correct 369 ms 26344 KB Output is correct
12 Correct 383 ms 26092 KB Output is correct
13 Correct 386 ms 26348 KB Output is correct
14 Correct 385 ms 26744 KB Output is correct

Subtask #3
21.0 / 21.0

# Verdict Execution time Memory Grader output
1 Correct 44 ms 6208 KB Output is correct
2 Correct 11 ms 1492 KB Output is correct
3 Correct 221 ms 14840 KB Output is correct
4 Correct 7 ms 980 KB Output is correct
5 Correct 251 ms 17472 KB Output is correct
6 Correct 0 ms 212 KB Output is correct
7 Correct 0 ms 212 KB Output is correct
8 Correct 122 ms 13732 KB Output is correct
9 Correct 122 ms 13676 KB Output is correct
10 Correct 188 ms 15340 KB Output is correct
11 Correct 197 ms 15420 KB Output is correct
12 Correct 198 ms 15768 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 212 KB Output is correct
19 Correct 192 ms 15784 KB Output is correct
20 Correct 191 ms 15480 KB Output is correct
21 Correct 200 ms 15432 KB Output is correct
22 Correct 205 ms 15436 KB Output is correct

Subtask #4
0 / 63.0

# Verdict Execution time Memory Grader output
1 Correct 42 ms 6092 KB Output is correct
2 Correct 3 ms 596 KB Output is correct
3 Correct 57 ms 8244 KB Output is correct
4 Correct 60 ms 8596 KB Output is correct
5 Correct 4 ms 980 KB Output is correct
6 Correct 6 ms 852 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 65 ms 11228 KB Output is correct
11 Correct 63 ms 11148 KB Output is correct
12 Correct 66 ms 11036 KB Output is correct
13 Correct 18 ms 2276 KB Output is correct
14 Correct 39 ms 5620 KB Output is correct
15 Correct 35 ms 5320 KB Output is correct
16 Correct 40 ms 5576 KB Output is correct
17 Correct 557 ms 34988 KB Output is correct
18 Correct 563 ms 34244 KB Output is correct
19 Correct 591 ms 34880 KB Output is correct
20 Correct 51 ms 8612 KB Output is correct
21 Correct 36 ms 5600 KB Output is correct
22 Correct 10 ms 1748 KB Output is correct
23 Correct 2 ms 468 KB Output is correct
24 Correct 0 ms 212 KB Output is correct
25 Correct 174 ms 17468 KB Output is correct
26 Correct 176 ms 17428 KB Output is correct
27 Correct 369 ms 26344 KB Output is correct
28 Correct 383 ms 26092 KB Output is correct
29 Correct 386 ms 26348 KB Output is correct
30 Correct 385 ms 26744 KB Output is correct
31 Correct 44 ms 6208 KB Output is correct
32 Correct 11 ms 1492 KB Output is correct
33 Correct 221 ms 14840 KB Output is correct
34 Correct 7 ms 980 KB Output is correct
35 Correct 251 ms 17472 KB Output is correct
36 Correct 0 ms 212 KB Output is correct
37 Correct 0 ms 212 KB Output is correct
38 Correct 122 ms 13732 KB Output is correct
39 Correct 122 ms 13676 KB Output is correct
40 Correct 188 ms 15340 KB Output is correct
41 Correct 197 ms 15420 KB Output is correct
42 Correct 198 ms 15768 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 212 KB Output is correct
49 Correct 192 ms 15784 KB Output is correct
50 Correct 191 ms 15480 KB Output is correct
51 Correct 200 ms 15432 KB Output is correct
52 Correct 205 ms 15436 KB Output is correct
53 Correct 637 ms 38104 KB Output is correct
54 Correct 628 ms 37840 KB Output is correct
55 Correct 624 ms 37344 KB Output is correct
56 Correct 63 ms 8396 KB Output is correct
57 Correct 60 ms 8760 KB Output is correct
58 Correct 489 ms 34292 KB Output is correct
59 Correct 560 ms 37152 KB Output is correct
60 Correct 532 ms 36764 KB Output is correct
61 Correct 471 ms 33036 KB Output is correct
62 Correct 519 ms 35632 KB Output is correct
63 Correct 547 ms 36612 KB Output is correct
64 Execution timed out 1085 ms 83408 KB Time limit exceeded
65 Halted 0 ms 0 KB -