Submission #831806

#	Time	Username	Problem	Language	Result	Execution time	Memory
831806		welleyth	Keys (IOI21_keys)	C++17	100 / 100	1553 ms	270140 KiB

keys

#include <bits/stdc++.h>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/pb_ds/assoc_container.hpp>
#pragma GCC optimize("O3")
using namespace std;
using namespace __gnu_pbds;
 
// typedef int int;
typedef pair<int,int>pairll;
 
#define N 150007
#define pb push_back
#define fr first
#define sc second

// #pragma GCC optimize("O3")
// #pragma GCC optimze("unroll-loops")
// #pragma GCC target("avx2")
 
int ans[2*N];
 
int p[2*N],f[2*N],n,m,d[2*N],sz[2*N];
bool fr[2*N];
 
set<pair<int,int>> v[2*N];
 
vector<int>v2[2*N];
 
vector<pairll> v1[2*N];
 
set<int> s[2*N],del[2*N],a[2*N];
 
int P(int x){
	return p[x] == x ? x : p[x] = P(p[x]);
}
 
void A(int x,int y){
	x=P(x);
	y=P(y);
	if(x == y) return;
	p[y] = x;
	if(v2[x].size()<v2[y].size()) swap(v2[x],v2[y]);

	for(auto& val : v2[y]) v2[x].push_back(val);
	if(v1[x].size()<v1[y].size()){
		swap(v1[x],v1[y]);
	}
	for(auto& val : v1[y]) v1[x].push_back(val);
	
	if(v[x].size()<v[y].size()){
		swap(s[x],s[y]);
		swap(v[x],v[y]);
		swap(a[x],a[y]);
	}
	for(auto&[col,to] : v[y]){
		if(s[x].count(col)){
			v2[x].push_back(to);
			// auto it = v[y].lower_bound(make_pair(col,-1));
			// while(it != v[y].end()){
			// 	if(it->first != col) break;
			// 	v2[x].push_back(it->second);
			// 	it++;
			// }
			// for(auto& val : v[y][it]) v2[x].push_back(val);
		}else if(s[y].count(col)){
			auto it = v[x].lower_bound(make_pair(col,-1));
			while(it != v[x].end()){
				if(it->first != col) break;
				v2[x].push_back(it->second);
				it++;
			}
			// for(auto& val : v[x][it]) v2[x].push_back(val);
			s[x].insert(col);
		}else{
			v[x].insert(make_pair(col,to));
			// if(v[y][it].size()>v[x][it].size()) swap(v[x][it],v[y][it]);
			// for(auto& val : v[y][it]) v[x][it].push_back(val);
		}
		// a[x].insert(it);
	}
	
	sz[x]+=sz[y];
	return ;
}
 
int S(int x,int y){
	x=P(x);
	if(f[x]==2)return x;
	if(f[x]==1)return 0;
	f[x]=2;
	while(v2[x].size()>0){
		int m1=v2[x].back();
		v2[x].pop_back();
		if(P(m1)!=P(x)){
			int g=S(m1,x);
			if(g!=0){
				if(x==g){	
					x=P(x);
				}else{
					A(x,y);
					return g;
				}
			}
		}
	}
	f[x]=1;
	return 0;
}
 
vector<int> find_reachable(vector<int> r, vector<int> u, vector<int> w, vector<int> c) {
	n=r.size();
	for(int i=1;i<=n;i++){
		d[i]=r[i-1];
		p[i]=i;
		s[i].insert(d[i]);
		sz[i]=1;
	}
	m=u.size();
	for(int i=0;i<m;i++){
		u[i]++;
		w[i]++;
		v[u[i]].insert({c[i],w[i]});
		v[w[i]].insert({c[i],u[i]});
		v1[u[i]].emplace_back(c[i],w[i]);
		v1[w[i]].emplace_back(c[i],u[i]);
		if(c[i]==d[u[i]]){
			v2[u[i]].pb(w[i]);
		}
 
		if(c[i]==d[w[i]]){
			v2[w[i]].pb(u[i]);
		}
		a[u[i]].insert(c[i]);
		a[w[i]].insert(c[i]);
	}
	for(int i=1;i<=n;i++){
		if(f[i]==0) S(i,i);
	}
	vector<int> values[2*N];
	for(int i=1;i<=n;i++){
		s[i].clear();
	}
	for(int i = 1; i <= n; i++){
		values[P(i)].push_back(d[i]);
	}
	for(int i = 1; i <= n; i++){
		sort(values[i].begin(),values[i].end());
		values[i].erase(unique(values[i].begin(),values[i].end()),values[i].end());
	}
	int mn=n;
	for(int i=1;i<=n;i++){
		if(p[i]!=i) continue;
		for(auto& it:v1[i]){
			auto itt = lower_bound(values[i].begin(),values[i].end(),it.first);
			bool have = (itt != values[i].end() && *itt == it.first);
			if(have && P(it.sc)!=i){
				fr[i]=1;
				break;
			}
		}
		if(fr[i]==0) mn=min(mn,sz[i]);
		//cout<<i<<" "<<P(i)<<endl;
	}
	for(int i=1;i<=n;i++){
		if(fr[P(i)]==0 && sz[P(i)]==mn) ans[i-1]=1;
	}
 
	return vector<int>(ans,ans+n);
}

• Subtask 1: 9 / 9
• Subtask 2: 11 / 11
• Subtask 3: 17 / 17
• Subtask 4: 30 / 30
• Subtask 5: 33 / 33