Submission #1046153

#	Time	Username	Problem	Language	Result	Execution time	Memory
1046153		Malix	Keys (IOI21_keys)	C++17	100 / 100	613 ms	157640 KiB

keys

#include "keys.h"
#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef vector<int> vi;
typedef vector<vi> vii;
typedef pair<int,int> pi;
typedef vector<pi> pii;
typedef tuple<int,int,int> tii;

#define REP(i,a,b) for(int i=a;i<b;i++)
#define F first
#define S second
#define PB push_back
#define MP make_pair
#define LSOne(s) ((s)&(-s))

ll INF=1e18+10;
int inf=1e9+10;
ll M=1e9+7;

int n,m;
vii a,d;
vi b,p,ke,com;
vector<set<int>> arr,keys,arr2;

void dfs(int x){
	for(auto u:a[x])if(p[u]==-1){
		p[u]=x;
		dfs(u);
	}
	b.PB(x);
}

void dfs2(int x,int k){
	for(auto u:arr2[x]){
		arr[k].insert(u);
		keys[k].insert(ke[u]);
		com[u]=k;
	}
	for(auto u:d[x])if(p[u]==-1){
		p[u]=x;
		dfs2(u,k);
	}
}

std::vector<int> find_reachable(std::vector<int> r, std::vector<int> u, std::vector<int> v, std::vector<int> c) {
	n=r.size();m=u.size();ke=r;
	a.resize(n);d.resize(n);
	REP(i,0,m){
		if(r[u[i]]==c[i]){
			a[u[i]].PB(v[i]);
			d[v[i]].PB(u[i]);
		}
		if(r[v[i]]==c[i]){
			a[v[i]].PB(u[i]);
			d[u[i]].PB(v[i]);
		}
	}
	vi ans(n,0);bool flag=0;
	REP(i,0,n)if(a[i].size()==0){
		ans[i]=1;
		flag=1;
	}
	if(flag)return ans;
	int k=n;int z=n;bool flag2=1;
	arr2.resize(n);
	REP(i,0,n)arr2[i].insert(i);

	while(flag2){
		p.clear();p.resize(z,-1);
		b.clear();
		REP(i,0,z)if(p[i]==-1){
			p[i]=-2;
			dfs(i);
		}
		reverse(b.begin(),b.end());
		p.clear();p.resize(n,-1);
		arr.clear();arr.resize(z);
		keys.clear();keys.resize(z);
		com.clear();com.resize(n);
		k=0;
		REP(i,0,z)if(p[b[i]]==-1){
			p[b[i]]=-2;
			dfs2(b[i],k++);
		}
		d.clear();d.resize(z);
		a.clear();a.resize(z);
		REP(i,0,m){
			int x=com[u[i]];
			int y=com[v[i]];
			if(x!=y){
				if(keys[x].count(c[i])==1){
					a[x].PB(y);d[y].PB(x);
				}
				if(keys[y].count(c[i])==1){
					a[y].PB(x);d[x].PB(y);
				}
			}
		}
		arr2=arr;
		if(k==z)flag2=0;
		z=k;
	}
	if(k==1){
		REP(i,0,n)ans[i]=1;
		return ans;
	}
	vi t(k,0);
	REP(i,0,m){
		int x=com[u[i]];
		int y=com[v[i]];
		if(x!=y){
			if(keys[x].count(c[i])==1)t[x]=1;
			if(keys[y].count(c[i])==1)t[y]=1;
		}
	}
	int mn=inf;
	vi brr;
	REP(i,0,k){
		if(t[i])continue;
		int as=arr[i].size();
		if(mn>as){
			mn=as;
			brr.clear();
			brr.PB(i);
		}
		else if(mn==as)brr.PB(i);
	}
	ans.clear();
	ans.resize(n,0);
	for(auto y:brr)for(auto x:arr[y])ans[x]=1;
	return ans;
}

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