Submission #998257

#	Time	Username	Problem	Language	Result	Execution time	Memory
998257		fuad27	Synchronization (JOI13_synchronization)	C++17	0 / 100	47 ms	13504 KiB

synchronization

#include <bits/stdc++.h>
using namespace std;
const int inf = 1e9;
const int N = 100'010;
int n, m, q;
vector<pair<int,int>> e;
vector<pair<int,int>> vals;
vector<int> g[N];
bool state[N];
int dfs(int at, int mx = inf, int p = -1) {
 // cout << at << " " << mx << endl;
  int ans=1;
  for(int ed:g[at]) {
    int to = (e[ed].first^e[ed].second^at);
    if(to == p)continue;
    if(vals[ed].first <= mx) {
      ans+=dfs(to, min(mx, vals[ed].second), at);
    }
  }
  return ans;
}
int main () { 

  cin.tie(0)->sync_with_stdio(0);
  cin >> n >> m >> q;
  for(int i = 1;i<n;i++) {
    int u, v;
    cin >> u >> v;
    e.push_back({u, v});
    vals.push_back({inf,-inf});
  }
  for(int i = 0;i<m;i++) {
    int c;
    cin >> c;
    c--;
    state[c]^=1;
    if(state[c] == 1 and vals[c].first == inf) {
      vals[c].first = i;
    }
    else vals[c].second = i;
  }
  for(int i = 0;i<n-1;i++) {
    if(vals[i].first == inf)continue;
    if(vals[i].second == -inf)vals[i].second = inf;
    g[e[i].first].push_back(i);
    g[e[i].second].push_back(i);
  }
  while(q--) {
    int a;
    cin >> a;
//    dfs(a);
    cout << dfs(a) << "\n";
//    cout << endl;
  }
}

• Subtask 1: 0 / 10
• Subtask 2: 0 / 20
• Subtask 3: 0 / 10
• Subtask 4: 0 / 20
• Subtask 5: 0 / 40