oj.uz

Submission #419155

# Submission time Handle Problem Language Result Execution time Memory
419155 2021-06-06T13:45:27 Z pauloamed Bridges (APIO19_bridges) C++14
100 / 100
 2996 ms 11380 KB 
#include<bits/stdc++.h>
using namespace std;

#define MAXN 100010
#define BLOCK 900
int sizes[MAXN]; // vetor com tamanhos
int parents[MAXN]; // vetor com pai de cada no

struct DSU{
  int numComponents;
  stack<pair<int,int>> lastPar, lastSize;
  vector<int> checkpoints;

  DSU(int n){
    lastPar = lastSize = stack<pair<int,int>>();
    checkpoints = {0};
    numComponents = n;
    for(int i = 1; i <= n; ++i){
        sizes[i] = 1; // tamanho inicial
        parents[i] = i; // valor padrao: cada um eh seu pai
    }
  }

  int find(int current){
      int newRoot = current; // variavel para guardar nova raiz
      while(newRoot != parents[newRoot]) // enquanto nao encontro no raiz
          newRoot = parents[newRoot]; // subo na arvore
      return newRoot; // retornamo a raiz da arvore
  }

  void onion(int a, int b){
      a = find(a); b = find(b); // unimos uma raiz a outra

      if(a == b) return; // se for a mesma raiz, nao tenho o que unir

      // uniao por tamanho
      if(sizes[a] < sizes[b]) swap(a,b); // quero unir "b" a "a"

      checkpoints.back()++;
      lastSize.push({a, sizes[a]});
      lastPar.push({b, parents[b]});

      sizes[a] += sizes[b]; // atualizando tamanho de "a"
      parents[b] = a; // pai de "b" eh "a"
      numComponents--;
  }

  void check(){
    checkpoints.push_back(0);
  }

  void rollback(){
    int x = checkpoints.back();
    numComponents += x;
    while (x--) {
      sizes[lastSize.top().first] = lastSize.top().second; lastSize.pop();
      parents[lastPar.top().first] = lastPar.top().second; lastPar.pop();
    }
    checkpoints.pop_back();
  }
};

vector<int> cost = {-1};
vector<pair<int,int>> edges = {{-1, -1}};
vector<pair<int, pair<int,int>>> qs;
/*
first: tipo 1 (update) ou 2 (query)
second:
  tipo 1: first (edge id), second (new weight)
  tipo 2: first (node id), second (cars weight)
*/

int main(){
  iostream::sync_with_stdio(false);
  cin.tie(NULL);

  int n, m; cin >> n >> m;

  for(int i = 0; i < m; ++i){
    int a, b, c; cin >> a >> b >> c;
    cost.push_back(c);
    edges.push_back({a, b});
  }

  int q; cin >> q;
  for(int i = 0; i < q; i++){
    int a, b, c; cin >> a >> b >> c;
    qs.push_back({a, {b, c}});
  }

  vector<int> ans(q, -1);
  for(int l = 0; l < q; l += BLOCK){
    DSU dsu(n);
    int r = min(q - 1, l + BLOCK - 1);

    //////////////////////////////////////////////////////////////

    // TODAS ARESTAS ALTERADAS ESTAO EM ALTERED_EDGES

    vector<pair<int,int>> safeEdges;
    vector<pair<int,int>> weightQueries;
    vector<int> unsafeQueries, unsafeEdges;

    // solving range
    vector<int> alteredEdges(m + 1);
    for(int i = l; i <= r; ++i){
      if(qs[i].first == 1){
        int edgeId = qs[i].second.first;
        alteredEdges[edgeId] = 1;
        unsafeQueries.push_back(i);
        unsafeEdges.push_back(edgeId);
      }else{
        int weight = qs[i].second.second;
        weightQueries.push_back({weight, i});
      }
    }

    for(int i = 1; i <= m; ++i){
      if(alteredEdges[i] == 0){
        safeEdges.push_back({cost[i], i});
      }
    }
    // TODAS ARESTAS NAO ALTERADAS ESTAO EM SAFE_EDGES
    // ORDENADAS DECRESCENTE PELO CUSTO


    sort(weightQueries.rbegin(), weightQueries.rend());
    sort(safeEdges.rbegin(), safeEdges.rend());

    sort(unsafeEdges.begin(), unsafeEdges.end());
    unsafeEdges.resize(unique(unsafeEdges.begin(), unsafeEdges.end()) - unsafeEdges.begin());

    int nextSafeEdge = 0;
    for(int i = 0; i < weightQueries.size(); ++i){
      int currWeight = weightQueries[i].first;

      // o carro saindo da cidade atual tem peso menor que ou igual ao peso da proxima
      // edge ainda nao adicionada?
      while(nextSafeEdge < safeEdges.size() && currWeight <= safeEdges[nextSafeEdge].first){
        int edgeId = safeEdges[nextSafeEdge].second;
        dsu.onion(edges[edgeId].first, edges[edgeId].second);
        nextSafeEdge++;
      }

      dsu.check();

      // adiciona os updt da range
      // quero adicionar todos os updt do bloco ate chegar em mim
      // e os q passam de mim so q com o peso original
      int currIndex = weightQueries[i].second;
      int currCity = qs[currIndex].second.first;


      for(auto x : unsafeEdges) alteredEdges[x] = 0;
      for(int j = 0; j < unsafeQueries.size(); j++){
        int k = unsafeQueries[j];
        int edgeId = qs[k].second.first;
        if(k > currIndex){
          if(alteredEdges[edgeId] == 0) alteredEdges[edgeId] = cost[edgeId];
        }else{
          int newWeight = qs[k].second.second;
          alteredEdges[edgeId] = newWeight;
        }
      }

      for(auto x : unsafeEdges){
        if(currWeight <= alteredEdges[x]){
          dsu.onion(edges[x].first, edges[x].second);
        }
      }

      ans[currIndex] = sizes[dsu.find(currCity)];
      dsu.rollback();
    }

    for(int j = 0; j < unsafeQueries.size(); j++){
      int k = unsafeQueries[j];
      int edgeId = qs[k].second.first;
      int newWeight = qs[k].second.second;
      cost[edgeId] = newWeight;
    }
  }

  for(auto x : ans) if(x != -1) cout << x << "\n";
}

Compilation message

bridges.cpp: In function 'int main()':
bridges.cpp:134:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  134 |     for(int i = 0; i < weightQueries.size(); ++i){
      |                    ~~^~~~~~~~~~~~~~~~~~~~~~
bridges.cpp:139:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  139 |       while(nextSafeEdge < safeEdges.size() && currWeight <= safeEdges[nextSafeEdge].first){
      |             ~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~
bridges.cpp:155:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  155 |       for(int j = 0; j < unsafeQueries.size(); j++){
      |                      ~~^~~~~~~~~~~~~~~~~~~~~~
bridges.cpp:176:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  176 |     for(int j = 0; j < unsafeQueries.size(); j++){
      |                    ~~^~~~~~~~~~~~~~~~~~~~~~

Subtask #1
13.0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 204 KB Output is correct
2 Correct 1 ms 204 KB Output is correct
3 Correct 45 ms 608 KB Output is correct
4 Correct 5 ms 588 KB Output is correct
5 Correct 26 ms 588 KB Output is correct
6 Correct 21 ms 592 KB Output is correct
7 Correct 27 ms 588 KB Output is correct
8 Correct 28 ms 592 KB Output is correct
9 Correct 33 ms 588 KB Output is correct
10 Correct 33 ms 592 KB Output is correct
11 Correct 28 ms 588 KB Output is correct
12 Correct 32 ms 588 KB Output is correct
13 Correct 35 ms 588 KB Output is correct
14 Correct 35 ms 608 KB Output is correct
15 Correct 29 ms 652 KB Output is correct
16 Correct 30 ms 588 KB Output is correct
17 Correct 30 ms 588 KB Output is correct

Subtask #2
16.0 / 16.0

# Verdict Execution time Memory Grader output
1 Correct 2020 ms 4424 KB Output is correct
2 Correct 1926 ms 4512 KB Output is correct
3 Correct 1960 ms 4476 KB Output is correct
4 Correct 2000 ms 4528 KB Output is correct
5 Correct 1928 ms 4424 KB Output is correct
6 Correct 2795 ms 5076 KB Output is correct
7 Correct 2760 ms 5064 KB Output is correct
8 Correct 2797 ms 5080 KB Output is correct
9 Correct 45 ms 1992 KB Output is correct
10 Correct 1970 ms 4552 KB Output is correct
11 Correct 1990 ms 4540 KB Output is correct
12 Correct 1629 ms 5000 KB Output is correct
13 Correct 1557 ms 4520 KB Output is correct

Subtask #3
17.0 / 17.0

# Verdict Execution time Memory Grader output
1 Correct 1574 ms 3488 KB Output is correct
2 Correct 1256 ms 2424 KB Output is correct
3 Correct 1834 ms 3624 KB Output is correct
4 Correct 1642 ms 3612 KB Output is correct
5 Correct 46 ms 2104 KB Output is correct
6 Correct 1969 ms 3580 KB Output is correct
7 Correct 1479 ms 3612 KB Output is correct
8 Correct 1339 ms 3508 KB Output is correct
9 Correct 1072 ms 3760 KB Output is correct
10 Correct 930 ms 3612 KB Output is correct
11 Correct 1020 ms 3484 KB Output is correct
12 Correct 912 ms 3480 KB Output is correct

Subtask #4
14.0 / 14.0

# Verdict Execution time Memory Grader output
1 Correct 1956 ms 5732 KB Output is correct
2 Correct 45 ms 2028 KB Output is correct
3 Correct 226 ms 3888 KB Output is correct
4 Correct 136 ms 3892 KB Output is correct
5 Correct 1892 ms 5716 KB Output is correct
6 Correct 1985 ms 6144 KB Output is correct
7 Correct 1933 ms 5868 KB Output is correct
8 Correct 1060 ms 4540 KB Output is correct
9 Correct 1010 ms 4444 KB Output is correct
10 Correct 1085 ms 4564 KB Output is correct
11 Correct 1583 ms 5120 KB Output is correct
12 Correct 1569 ms 5308 KB Output is correct
13 Correct 1520 ms 5300 KB Output is correct
14 Correct 1655 ms 5692 KB Output is correct
15 Correct 1754 ms 5948 KB Output is correct
16 Correct 1944 ms 5876 KB Output is correct
17 Correct 1907 ms 5664 KB Output is correct
18 Correct 1982 ms 5904 KB Output is correct
19 Correct 1969 ms 5740 KB Output is correct
20 Correct 1647 ms 5440 KB Output is correct
21 Correct 1699 ms 5336 KB Output is correct
22 Correct 1866 ms 5572 KB Output is correct
23 Correct 1747 ms 5184 KB Output is correct

Subtask #5
13.0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 2020 ms 4424 KB Output is correct
2 Correct 1926 ms 4512 KB Output is correct
3 Correct 1960 ms 4476 KB Output is correct
4 Correct 2000 ms 4528 KB Output is correct
5 Correct 1928 ms 4424 KB Output is correct
6 Correct 2795 ms 5076 KB Output is correct
7 Correct 2760 ms 5064 KB Output is correct
8 Correct 2797 ms 5080 KB Output is correct
9 Correct 45 ms 1992 KB Output is correct
10 Correct 1970 ms 4552 KB Output is correct
11 Correct 1990 ms 4540 KB Output is correct
12 Correct 1629 ms 5000 KB Output is correct
13 Correct 1557 ms 4520 KB Output is correct
14 Correct 1574 ms 3488 KB Output is correct
15 Correct 1256 ms 2424 KB Output is correct
16 Correct 1834 ms 3624 KB Output is correct
17 Correct 1642 ms 3612 KB Output is correct
18 Correct 46 ms 2104 KB Output is correct
19 Correct 1969 ms 3580 KB Output is correct
20 Correct 1479 ms 3612 KB Output is correct
21 Correct 1339 ms 3508 KB Output is correct
22 Correct 1072 ms 3760 KB Output is correct
23 Correct 930 ms 3612 KB Output is correct
24 Correct 1020 ms 3484 KB Output is correct
25 Correct 912 ms 3480 KB Output is correct
26 Correct 2072 ms 4524 KB Output is correct
27 Correct 2545 ms 4556 KB Output is correct
28 Correct 2222 ms 4540 KB Output is correct
29 Correct 1695 ms 4472 KB Output is correct
30 Correct 2456 ms 4552 KB Output is correct
31 Correct 2508 ms 4544 KB Output is correct
32 Correct 2637 ms 4552 KB Output is correct
33 Correct 2171 ms 4428 KB Output is correct
34 Correct 2206 ms 4544 KB Output is correct
35 Correct 2115 ms 4416 KB Output is correct
36 Correct 1641 ms 4416 KB Output is correct
37 Correct 1636 ms 4420 KB Output is correct
38 Correct 1646 ms 4528 KB Output is correct
39 Correct 1258 ms 4548 KB Output is correct
40 Correct 1219 ms 4548 KB Output is correct
41 Correct 1254 ms 4556 KB Output is correct
42 Correct 1224 ms 4804 KB Output is correct
43 Correct 1265 ms 4792 KB Output is correct
44 Correct 1277 ms 4792 KB Output is correct

Subtask #6
27.0 / 27.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 204 KB Output is correct
2 Correct 1 ms 204 KB Output is correct
3 Correct 45 ms 608 KB Output is correct
4 Correct 5 ms 588 KB Output is correct
5 Correct 26 ms 588 KB Output is correct
6 Correct 21 ms 592 KB Output is correct
7 Correct 27 ms 588 KB Output is correct
8 Correct 28 ms 592 KB Output is correct
9 Correct 33 ms 588 KB Output is correct
10 Correct 33 ms 592 KB Output is correct
11 Correct 28 ms 588 KB Output is correct
12 Correct 32 ms 588 KB Output is correct
13 Correct 35 ms 588 KB Output is correct
14 Correct 35 ms 608 KB Output is correct
15 Correct 29 ms 652 KB Output is correct
16 Correct 30 ms 588 KB Output is correct
17 Correct 30 ms 588 KB Output is correct
18 Correct 2020 ms 4424 KB Output is correct
19 Correct 1926 ms 4512 KB Output is correct
20 Correct 1960 ms 4476 KB Output is correct
21 Correct 2000 ms 4528 KB Output is correct
22 Correct 1928 ms 4424 KB Output is correct
23 Correct 2795 ms 5076 KB Output is correct
24 Correct 2760 ms 5064 KB Output is correct
25 Correct 2797 ms 5080 KB Output is correct
26 Correct 45 ms 1992 KB Output is correct
27 Correct 1970 ms 4552 KB Output is correct
28 Correct 1990 ms 4540 KB Output is correct
29 Correct 1629 ms 5000 KB Output is correct
30 Correct 1557 ms 4520 KB Output is correct
31 Correct 1574 ms 3488 KB Output is correct
32 Correct 1256 ms 2424 KB Output is correct
33 Correct 1834 ms 3624 KB Output is correct
34 Correct 1642 ms 3612 KB Output is correct
35 Correct 46 ms 2104 KB Output is correct
36 Correct 1969 ms 3580 KB Output is correct
37 Correct 1479 ms 3612 KB Output is correct
38 Correct 1339 ms 3508 KB Output is correct
39 Correct 1072 ms 3760 KB Output is correct
40 Correct 930 ms 3612 KB Output is correct
41 Correct 1020 ms 3484 KB Output is correct
42 Correct 912 ms 3480 KB Output is correct
43 Correct 1956 ms 5732 KB Output is correct
44 Correct 45 ms 2028 KB Output is correct
45 Correct 226 ms 3888 KB Output is correct
46 Correct 136 ms 3892 KB Output is correct
47 Correct 1892 ms 5716 KB Output is correct
48 Correct 1985 ms 6144 KB Output is correct
49 Correct 1933 ms 5868 KB Output is correct
50 Correct 1060 ms 4540 KB Output is correct
51 Correct 1010 ms 4444 KB Output is correct
52 Correct 1085 ms 4564 KB Output is correct
53 Correct 1583 ms 5120 KB Output is correct
54 Correct 1569 ms 5308 KB Output is correct
55 Correct 1520 ms 5300 KB Output is correct
56 Correct 1655 ms 5692 KB Output is correct
57 Correct 1754 ms 5948 KB Output is correct
58 Correct 1944 ms 5876 KB Output is correct
59 Correct 1907 ms 5664 KB Output is correct
60 Correct 1982 ms 5904 KB Output is correct
61 Correct 1969 ms 5740 KB Output is correct
62 Correct 1647 ms 5440 KB Output is correct
63 Correct 1699 ms 5336 KB Output is correct
64 Correct 1866 ms 5572 KB Output is correct
65 Correct 1747 ms 5184 KB Output is correct
66 Correct 2072 ms 4524 KB Output is correct
67 Correct 2545 ms 4556 KB Output is correct
68 Correct 2222 ms 4540 KB Output is correct
69 Correct 1695 ms 4472 KB Output is correct
70 Correct 2456 ms 4552 KB Output is correct
71 Correct 2508 ms 4544 KB Output is correct
72 Correct 2637 ms 4552 KB Output is correct
73 Correct 2171 ms 4428 KB Output is correct
74 Correct 2206 ms 4544 KB Output is correct
75 Correct 2115 ms 4416 KB Output is correct
76 Correct 1641 ms 4416 KB Output is correct
77 Correct 1636 ms 4420 KB Output is correct
78 Correct 1646 ms 4528 KB Output is correct
79 Correct 1258 ms 4548 KB Output is correct
80 Correct 1219 ms 4548 KB Output is correct
81 Correct 1254 ms 4556 KB Output is correct
82 Correct 1224 ms 4804 KB Output is correct
83 Correct 1265 ms 4792 KB Output is correct
84 Correct 1277 ms 4792 KB Output is correct
85 Correct 2566 ms 7572 KB Output is correct
86 Correct 246 ms 5760 KB Output is correct
87 Correct 185 ms 6076 KB Output is correct
88 Correct 2349 ms 9976 KB Output is correct
89 Correct 2580 ms 11380 KB Output is correct
90 Correct 2461 ms 9276 KB Output is correct
91 Correct 2219 ms 7136 KB Output is correct
92 Correct 2140 ms 7220 KB Output is correct
93 Correct 2996 ms 7536 KB Output is correct
94 Correct 2376 ms 8552 KB Output is correct
95 Correct 2330 ms 8680 KB Output is correct
96 Correct 2374 ms 8396 KB Output is correct
97 Correct 2088 ms 8288 KB Output is correct
98 Correct 2089 ms 8852 KB Output is correct
99 Correct 2644 ms 9448 KB Output is correct
100 Correct 2606 ms 9428 KB Output is correct
101 Correct 2729 ms 9628 KB Output is correct
102 Correct 2645 ms 9620 KB Output is correct
103 Correct 2547 ms 8800 KB Output is correct
104 Correct 2602 ms 8540 KB Output is correct
105 Correct 2004 ms 8780 KB Output is correct
106 Correct 1710 ms 8592 KB Output is correct
107 Correct 2004 ms 8648 KB Output is correct
108 Correct 2560 ms 9180 KB Output is correct
109 Correct 2382 ms 7420 KB Output is correct