Submission #1215506

#	Time	Username	Problem	Language	Result	Execution time	Memory
1215506		dosts	Keys (IOI21_keys)	C++20	20 / 100	3098 ms	412056 KiB

keys

#include <bits/stdc++.h>
#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("avx2")
//#define int long long
#define pii pair<int,int>
#define vi vector<int>
#define ff first
#define ss second
#define sp << " " <<
#define all(x) x.begin(),x.end()
#define big(x) ((int)(x.size()))
using namespace std;
const int MOD = 1e9+7, LIM = 3e5+1, inf = 2e9;
vi edges[LIM],egdes[LIM], vis(LIM,0), col(LIM);
vi order;

void topo(int node) {
	if (vis[node]) return;
	vis[node] = 1;
	for (auto it : edges[node]) {
		topo(it);
	}
	order.push_back(node);
}

int color(int node,int c) {
	if (vis[node]) return 0;
	vis[node] = 1;
	col[node] = c;
	int ans = 1;
	for (auto it : egdes[node]) ans+=color(it,c);
	return ans;
}

std::vector<int> find_reachable(std::vector<int> r, std::vector<int> u, std::vector<int> v, std::vector<int> c) {
	int n = r.size(),m = u.size();
	vi canreach[n];
	set<int> cols[n];
	vector<pii> edg[n];
	for (int i = 0;i<m;i++) {
		if (r[u[i]] == c[i]) canreach[v[i]].push_back(u[i]);
		if (r[v[i]] == c[i]) canreach[u[i]].push_back(v[i]);
		edg[u[i]].push_back({v[i],c[i]});
		edg[v[i]].push_back({u[i],c[i]});
	}
	queue<pii> q;
	for (int i = 0;i<n;i++) q.push({i,r[i]}),cols[i].insert(r[i]);
	while (!q.empty()) {
		pii f = q.front();
		q.pop();
		int city = f.ff,col = f.ss;
		for (auto it : canreach[city]) {
			if (!cols[it].count(col)) {
				cols[it].insert(col);
				q.push({it,col});
			}
		}
		for (auto it : edg[city]) {
			if (it.ss == col) {
				canreach[it.ff].push_back(city);
				for (auto it : cols[it.ff]) {
					if (!cols[city].count(it)) {
						cols[city].insert(it);
						q.push({city,it});
					}
				}
			}
		}
	}
	for (int i = 0;i<n;i++) {
		for (auto it : edg[i]) {
			if (cols[i].count(it.ss)) {
				edges[i].push_back(it.ff);
				egdes[it.ff].push_back(i);
			}
		}
	}
	vi ans(n,0);
	int fnd = 0;
	for (int i = 0;i<n;i++) {
		if (edges[i].empty()) {
			fnd = 1;
			ans[i] = 1;
		}
	}
	if (fnd) return ans;
	for (int i = 0;i<n;i++) topo(i);
	reverse(all(order));
	vis.assign(n,0);
	int cc = 0;
	vi szs;
	for (int i = 0;i<n;i++) {
		if (!vis[order[i]]) {
			szs.push_back(color(order[i],cc++));
		}
	}
	reverse(all(order));
	for (auto i : order) {
		for (auto it : edges[i]) {
			if (col[i] != col[it]) {
				szs[col[i]]+=szs[col[it]];
			}
		}
	}
	int x = inf;
	for (int i=0;i<n;i++) {
		if (szs[col[i]] < x) {
			x = szs[col[i]];
		}
	}
	for (int i = 0;i<n;i++) {
		if (szs[col[i]] == x) ans[i] = 1;
	}
	return ans;
}

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