Submission #403303

#	Time	Username	Problem	Language	Result	Execution time	Memory
403303		oolimry	족보 (KOI18_family)	C++17	100 / 100	544 ms	59876 KiB

family

#include <bits/stdc++.h>
#define all(x) (x).begin(), (x).end()
using namespace std;
typedef pair<int,int> ii;

int n1, n2, K; 
vector<int> child[2][300005];
int num[2][300005];
int rep[2][300005];
struct check{ int num, u, t; };
vector<check> stuff;

void dfs(int t, int u){
	if(u != 0 && u <= K){
		num[t][u] = 1;
		rep[t][u] = u;
	}
	else{
		for(int v : child[t][u]){
			dfs(t, v);
			num[t][u] += num[t][v];
			rep[t][u] = rep[t][v];
		}
		if(num[t][u] > 1) stuff.push_back({num[t][u], u, t});
		///idk why child[t][u].size() > 1 is needed .-.
	}
}

int p[300005];
int sz[300005];
int findSet(int u){
	if(p[u] == u) return u;
	else return p[u] = findSet(p[u]);
}
void unionSet(int u, int v){
	u = findSet(u), v = findSet(v);
	if(u == v) return;
	if(u&1) swap(u,v);
	p[u] = v;
	sz[v] += sz[u];
}
int getSz(int u){
	return sz[findSet(u)];
}

int main(){
	//freopen("i.txt","r",stdin);
	cin >> n1 >> n2 >> K;
	
	for(int i = 1;i <= n1;i++){
		int a; cin >> a;
		child[0][a].push_back(i);
	}
	for(int i = 1;i <= n2;i++){
		int a; cin >> a;
		child[1][a].push_back(i);
	}

	dfs(0, 0); dfs(1, 0);
	
	for(int i = 1;i <= K;i++){
		p[i] = i;
		sz[i] = 1;
	}
		
	sort(all(stuff), [&](check a, check b){ return a.num < b.num; });
	
	for(check C : stuff){
		
		for(int v : child[C.t][C.u]){
			unionSet(rep[C.t][C.u], rep[C.t][v]);
		} 
		if((int) child[C.t][C.u].size() <= 1) continue;
		if(getSz(rep[C.t][C.u]) != C.num){
			cout << "NO";
			return 0;
		}
	}
	
	
	cout << "YES";
}

• Subtask 1: 17 / 17
• Subtask 2: 27 / 27
• Subtask 3: 15 / 15
• Subtask 4: 41 / 41