Submission #440162

#	Time	Username	Problem	Language	Result	Execution time	Memory
440162		koioi.org-koosaga	Keys (IOI21_keys)	C++17	37 / 100	3055 ms	149824 KiB

keys

#include <bits/stdc++.h>
#define sz(v) ((int)(v).size())
#define all(v) (v).begin(), (v).end()
using namespace std;
using lint = long long;
using pi = pair<int, int>;
const int MAXN = 600005;
 
struct disj{
	int pa[MAXN];
	void init(){
		iota(pa, pa + MAXN, 0);
	}
	int find(int x){
		return pa[x] = (pa[x] == x ? x : find(pa[x]));
	}
	bool uni(int p, int q){
		p = find(p);
		q = find(q);
		if(p == q) return 0;
		pa[q] = p; return 1;
	}
}disj;
 
vector<int> bycmp[MAXN];
set<int> keys[MAXN];
set<pi> gph[2][MAXN];
int comp[MAXN], nxt[MAXN];
int idx[MAXN], sz[MAXN];

int find(int x){
	return comp[x] = (comp[x] == x ? x : find(comp[x]));
}
 
void merge_to(int u, int v){
	u = find(u);
	if(u == v) return;
	comp[u] = v;
	int ov = v;
	if(sz[u] > sz[v]) swap(u, v);
	sz[v] += sz[u];
	for(auto &i : keys[idx[u]]){
		if(keys[idx[v]].find(i) == keys[idx[v]].end()){
			keys[idx[v]].insert(i);
			auto it = gph[0][idx[v]].lower_bound(pi(i, -1));
			while(it != gph[0][idx[v]].end() && it->first == i){
				gph[1][idx[v]].insert(*it);
				it = gph[0][idx[v]].erase(it);
			}
		}
	}
	for(auto &i : gph[1][idx[u]]) gph[1][idx[v]].insert(i);
	for(auto &[c, d] : gph[0][idx[u]]){
		if(keys[idx[v]].find(c) != keys[idx[v]].end()){
			gph[1][idx[v]].emplace(c, d);
		}
		else gph[0][idx[v]].emplace(c, d);
	}
	keys[idx[u]].clear();
	gph[0][idx[u]].clear();
	gph[1][idx[u]].clear();
	idx[ov] = idx[v];
}
 
std::vector<int> find_reachable(std::vector<int> r, std::vector<int> u, std::vector<int> v, std::vector<int> c) {	
	int n = sz(r);
	for(int i = 0; i < n; i++) keys[i].insert(r[i]);
	for(int i = 0; i < sz(u); i++){
		gph[c[i] == r[u[i]]][u[i]].emplace(c[i], v[i]);
		gph[c[i] == r[v[i]]][v[i]].emplace(c[i], u[i]);
	}
	disj.init();
	iota(idx, idx + MAXN, 0);
	fill(sz, sz + MAXN, 1);
	iota(comp, comp + MAXN, 0);
	vector<int> ans(n, 1e9);
	for(int i = 0; i < n; i++){
		nxt[i] = i;
		if(sz(gph[1][i])) nxt[i] = gph[1][i].begin()->second;
	}
	if(count(all(ans), 1) != 0) return ans;
	for(int i = 0; i < n; i++){
		if(find(i) != i) continue;
		if(i == find(nxt[i])) continue;
		if(!disj.uni(i, nxt[i])){
			for(int j = find(nxt[i]); find(j) != find(n); j = find(nxt[j])){
				merge_to(j, n);
			}
			disj.uni(i, n);
			auto it = gph[1][idx[n]].begin();
			nxt[n] = n;
			while(it != gph[1][idx[n]].end()){
				int k, v;
				tie(k, v) = *it;
				if(find(v) == find(n)) it = gph[1][idx[n]].erase(it);
				else{	
					nxt[n] = find(v);
					break;
				}
			}
			n++;
		}
	}
	for(int j = 0; j < sz(ans); j++){
		bycmp[find(j)].push_back(j);
	}
	fill(all(ans), 1e9);
	for(int j = 0; j < n; j++){
		if(sz(bycmp[j]) && find(nxt[j]) == find(j)){
			for(auto &i : bycmp[j]){
				if(i < sz(ans)) ans[i] = sz(bycmp[j]);
			}
		}
	}
	int val = *min_element(all(ans));
	for(auto &i : ans){
		i = (i == val);
	}
	return ans;
}

• Subtask 1: 9 / 9
• Subtask 2: 11 / 11
• Subtask 3: 17 / 17
• Subtask 4: 0 / 30
• Subtask 5: 0 / 33