Submission #416010

#	Time	Username	Problem	Language	Result	Execution time	Memory
416010		pauloamed	Bitaro’s Party (JOI18_bitaro)	C++14	7 / 100	2068 ms	239732 KiB

bitaro

#include<bits/stdc++.h>
using namespace std;

#define MAXN 100010

int n;
vector<int> v[MAXN];
vector<int> rv[MAXN];

int fullSolution(int x, vector<bool> &on){
  vector<int> pd(n, -1);

  pd[x] = 0;
  for(int i = x - 1; i >= 0; --i){
    for(auto y : v[i]){
      if(y <= x && pd[y] != -1){
        pd[i] = max(pd[i], pd[y] + 1);
      }
    }
  }

  int ans = -1;
  for(int i = 0; i <= x; ++i){
    // cout << pd[i] << endl;
    if(on[i]) ans = max(ans, pd[i]);
  }
  return ans;
}


int main(){
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  int m, q; cin >> n >> m >> q;
  for(int i = 0; i < m; ++i){
    int a, b; cin >> a >> b; a--, b--;
    if(a > b) swap(a, b);
    v[a].push_back(b);
    rv[b].push_back(a);
  }

  int block = sqrt(n) + 3;
  // cout << block << endl;

  vector<vector<pair<int,int>>> bestDists(n);
  for(int i = 0; i < n; ++i){
    vector<pair<int,int>> tmp;
    for(auto x : rv[i]){
      for(auto y : bestDists[x]) tmp.push_back(y);
    }

    for(auto &x : tmp) x.first++;
    tmp.push_back({0, i});

    // cout << i << endl;
    // for(auto x : tmp){
    //   cout << x.first << " " << x.second << ", ";
    // }cout << endl;

    vector<bool> occour(n);
    sort(tmp.rbegin(), tmp.rend());
    for(int j = 0; j < tmp.size() && bestDists[i].size() < block; ++j){
      if(!occour[tmp[j].second]){
        occour[tmp[j].second] = true;
        bestDists[i].push_back(tmp[j]);
      }
    }

    // cout << i << endl;
    // for(auto x : bestDists[i]){
    //   cout << x.first << " " << x.second << ", ";
    // }cout << endl;
  }

  vector<bool> on(n, true);
  while(q--){
    int x, y; cin >> x >> y; x--;
    vector<int> currOff;
    while(y--){
      int z; cin >> z; z--;
      on[z] = false;
      currOff.push_back(z);
    }

    int ans = -1;
    for(auto z : bestDists[x]){
      if(on[z.second]){
        ans = z.first; break;
      }
    }

    if(ans == -1) ans = fullSolution(x, on);
    cout << ans << "\n";
    for(auto z : currOff) on[z] = true;
  }
}

Compilation message (stderr)

bitaro.cpp: In function 'int main()':
bitaro.cpp:62:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   62 |     for(int j = 0; j < tmp.size() && bestDists[i].size() < block; ++j){
      |                    ~~^~~~~~~~~~~~
bitaro.cpp:62:58: warning: comparison of integer expressions of different signedness: 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   62 |     for(int j = 0; j < tmp.size() && bestDists[i].size() < block; ++j){
      |                                      ~~~~~~~~~~~~~~~~~~~~^~~~~~~

• Subtask 1: 7 / 7
• Subtask 2: 0 / 7
• Subtask 3: 0 / 86