제출 #1276517

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1276517		WH8	Railway (BOI17_railway)	C++20	52 / 100	204 ms	46608 KiB

railway

#include <bits/stdc++.h>
using namespace std;
#define int long long 
#define pll pair<int, int>
#define mp make_pair
#define pb push_back
#define f first
#define s second

int n,m,k;
vector<int> num(100005), ans(100005, 0);
vector<map<int,int>> v(100005);
vector<vector<pair<int,int>>> al(100005);
vector<vector<int>> here(100005);

vector<int> abv;

void dfs(int x, int pind){
	for(int it:here[x]){
		v[x][it]++;
		ans[x]++;
	}
	for(auto [to, ind] : al[x]){
		if(ind==pind)continue;
		dfs(to, ind);
		// merge into v[x]
		if(v[to].size() > v[x].size())swap(v[to], v[x]);
		ans[x]+=ans[to];
		for(auto [dep, amt] : v[to]){
			v[x][dep]+=amt;
			if(v[x][dep]>amt){
				ans[x]--;
			}
			if(v[x][dep]==num[dep]){
				ans[x]--;
			}
		}

	}
	if(ans[x] >= k){
		abv.pb(pind);	
	}
	//~ printf("at %lld, ans is %lld\n", x, ans[x]);
	//~ for(auto [dep, amt]:v[x]){
		//~ printf("(%lld, %lld) ",dep, amt);
	//~ }
	//~ cout<<endl;
}

signed main(){
	cin>>n>>m>>k;
	for(int i=1;i<=n-1;i++){
		int a,b;cin>>a>>b;
		al[a].pb({b,i});
		al[b].pb({a,i});
	}
	for(int i=0;i<m;i++){
		int si;cin>>si;
		for(int j=0;j<si;j++){
			int ep;cin>>ep;
			here[ep].pb(i);
		}
		num[i]=si;
	}
	dfs(1, -1);
	cout<<abv.size()<<"\n";
	sort(abv.begin(),abv.end());
	for(auto it:abv){
		cout<<it<<" ";
	}
}

• Subtask 1: 0 / 8
• Subtask 2: 0 / 15
• Subtask 3: 7 / 7
• Subtask 4: 29 / 29
• Subtask 5: 16 / 16
• Subtask 6: 0 / 25