Submission #1260363

#	Time	Username	Problem	Language	Result	Execution time	Memory
1260363		abdelhakim	Spring cleaning (CEOI20_cleaning)	C++20	17 / 100	136 ms	13076 KiB

cleaning

#include <bits/stdc++.h>
#define ll long long
#define dbg(x) cerr << #x << ' ' <<  x << endl; 
#define inf 1e18
using namespace std;

void printvec(vector<ll>& vec)
{
  for (auto &&e : vec)
  {
    cout << e << ' ';
  }
  cout << endl;
}
vector<ll> value;
ll solve(vector<vector<ll>>& adj, ll node, ll par, ll& ans,vector<pair<ll,ll>>& parr)
{
  if(node!=par && adj[node].size()==1)
  {
    parr[node]={par,1};
    if(node!=0)
    {
      if(parr[node].second==0) ans+=2;
      else ans++;
    }
    return 1;
  }
  ll sm=0;
  for (auto &&e : adj[node])
  {
    if(e==par)continue;
    ll val=solve(adj,e,node,ans,parr);
    sm+=val;
  }
  if(adj[node].size()==1 && node==0) sm++;
  parr[node]={par,sm%2};
  if(node!=0)
  {
    if(parr[node].second==0) ans+=2;
    else ans++;
  }
  return sm;
}
void dfs(ll node, ll par, ll cur,vector<vector<ll>>& adj, vector<pair<ll,ll>>& parr)
{
  if(node!=0)
  {
    if(parr[node].second)
    {
      cur++;
    }
    else cur--;
  }
  value[node]=cur;
  for (auto &&e : adj[node])
  {
    if(e==par) continue;
    dfs(e,node,cur,adj,parr); 
  }
}
void tl3(ll node, vector<pair<ll,ll>>& parr, ll& ans)
{
  while(node!=0)
  {
    if(parr[node].second==0)ans--;
    else ans++;
    parr[node].second^=1;
    node=parr[node].first;
  }
}
int main()
{
  cin.tie(0);
  ios_base::sync_with_stdio(false);
  ll n, q;
  cin>>n>>q;
  vector<vector<ll>> adj(n);
  value.resize(n);
  for (int i=0;i<n-1;i++)
  {
    ll u, v;
    cin>>u>>v;
    u--;v--;
    adj[u].push_back(v);
    adj[v].push_back(u);
  }
  ll old=0;
  ll leaves=0;
  for (int i=0;i<n;i++)
  {
    leaves+=adj[i].size()==1;
  }
  vector<pair<ll,ll>> parr(n);
  solve(adj,0,0,old,parr);
  dfs(0,0,0,adj,parr);
  while(q--)
  {
    ll d;
    cin>>d;
    vector<ll> v;
    vector<ll> arr;
    ll ans=old;
    ll val=leaves;
    for (int i=0;i<d;i++)
    {
      ll nd;
      cin>>nd;
      nd--;
      if(adj[nd].size()!=1)
      {
        val++;
        ans+=value[nd];
      }
      ans++;
    }
    if(val%2) cout<<-1<<endl;
    else cout << ans << endl;
  }
}

• Subtask 1: 0 / 0
• Subtask 2: 0 / 9
• Subtask 3: 0 / 9
• Subtask 4: 0 / 16
• Subtask 5: 0 / 19
• Subtask 6: 17 / 17
• Subtask 7: 0 / 30