Submission #521890

#	Time	Username	Problem	Language	Result	Execution time	Memory
521890		boykut	Easter Eggs (info1cup17_eastereggs)	C++14	26.40 / 100	808 ms	1608 KiB

eastereggs

#include <bits/stdc++.h>
#include "grader.h"

using namespace std;

int findEgg (int N, vector < pair < int, int > > bridges){

	vector<int> par(1 + N);
	vector<vector<int>> g(1 + N);
	for (auto it : bridges) {
		int a, b;
		tie(a, b) = it;
		g[a].push_back(b);
		g[b].push_back(a);
	}
	set<int> st;
	for (int i = 1; i <= N; i++)
		st.insert(i);
	while (true) {
		vector<int> comp;
		function<void(int, int)> dfs = [&](int v, int p) {
			comp.push_back(v);
			for (auto to : g[v]) {
				if (to == p) continue;
				if (!st.count(to)) continue;
				dfs(to, v);
			}
		};
		vector<vector<int>> v;
		for (auto it : st) {
			while (!comp.empty()) comp.pop_back();
			dfs(it, -1);
			v.push_back(comp);
		}
		sort(v.begin(), v.end(), [&](vector<int> a, vector<int> b) {
			return a.size() > b.size();
		});
		vector<int> Q;
		for (int i = 0; i < max(1,min((int)v[0].size(), (int)st.size()/2)); i++) {
			Q.push_back(v[0][i]);
		}
		if (query(Q) == 1) {
			if (Q.size() == 1) return Q[0];
			set<int> h;
			for (auto it : Q) h.insert(it);
			for (int i = 1; i <= N; i++) if (st.count(i) && !h.count(i)) st.erase(i);
		} else {
			for (auto it : Q) st.erase(it);
		}
	}
	return -1;
}

• Subtask 1: 26.4 / 40
• Subtask 2: 0 / 40
• Subtask 3: 0 / 20