Submission #1172195

#	Time	Username	Problem	Language	Result	Execution time	Memory
1172195		gyg	Keys (IOI21_keys)	C++20	20 / 100	3096 ms	31812 KiB

keys

#include "keys.h"
#include <bits/stdc++.h>
using namespace std;
#define vec vector
#define arr array 
#define pii pair<int, int>
#define fir first 
#define sec second 
const int N = 3e5 + 5;

// Zero indexing

int n;
arr<int, N> cl;
arr<vec<pii>, N> adj;

arr<bool, N> ngh_vs;
void ngh_dfs(int u, int src) {
	ngh_vs[u] = true;
	for (pii x : adj[u]) {
		if (x.sec != cl[src]) continue;
		if (ngh_vs[x.fir]) continue;
		ngh_dfs(x.fir, src);
	}
}
arr<vec<int>, N> ngh;
void ngh_cmp() {
	for (int u = 0; u < n; u++) {
		ngh_vs.fill(false);
		ngh_dfs(u, u);
		for (int v = 0; v < n; v++)
			if (ngh_vs[v]) ngh[u].push_back(v);
	}

	// for (int u = 0; u < n; u++) {
	// 	cout << u << ": ";
	// 	for (int v : ngh[u]) cout << v << " ";
	// 	cout << '\n';
	// }
}

arr<bool, N> cnt_vs;
void cnt_dfs(int u) {
	cnt_vs[u] = true;
	for (int v : ngh[u])
		if (!cnt_vs[v]) cnt_dfs(v);
}

arr<int, N> cnt;
void cnt_cmp() {
	for (int u = 0; u < n; u++) {
		cnt_vs.fill(false);
		cnt_dfs(u);
		cnt[u] = accumulate(cnt_vs.begin(), cnt_vs.begin() + n, 0);
	}
}

vec<int> find_reachable(vec<int> _cl, vec<int> _u, vec<int> _v, vec<int> _c) {
	n = _cl.size();
	for (int u = 0; u < n; u++) cl[u] = _cl[u];
	for (int i = 0; i < _u.size(); i++) {
		int u = _u[i], v = _v[i], c = _c[i];
		adj[u].push_back({v, c});
		adj[v].push_back({u, c});
	}
	
	ngh_cmp();
	cnt_cmp();

	vec<int> ans(n);
	int mn = *min_element(cnt.begin(), cnt.begin() + n);
	for (int u = 0; u < n; u++)	
		if (cnt[u] == mn) ans[u] = 1;
	return ans;
}

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