제출 #389297

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
389297		8e7	Easter Eggs (info1cup17_eastereggs)	C++14	100 / 100	26 ms	580 KiB

eastereggs

//Challenge: Accepted
#include <iostream>
#include <algorithm>
#include <utility>
#include <vector>
#include "grader.h"
#define ll long long
#define maxn 550
#define ff first
#define ss second
#define io ios_base::sync_with_stdio(0);cin.tie(0);
#define pii pair<int, int>
using namespace std;
//#include <bits/extc++.h>
//using namespace __gnu_pbds;
//template<lcass T> using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
//find by order, order of key
namespace{
	vector<int> adj[maxn];
	vector<int> que;
	bool found[maxn];
	bool poss[maxn], cost[maxn];
}

void dfs(int n, int par, int &num) {
	if (num == 0) return;
	num -= cost[n];
	found[n] = 1;
	que.push_back(n);
	for (int v:adj[n]) {
		if (v != par) {
			dfs(v, n, num);
		}
	}
}
int findEgg(int n, vector < pair < int, int > > bridges) {
	for (int i = 1;i <= n;i++) poss[i] = 1, cost[i] = 1, adj[i].clear();
	for (auto ed:bridges) {
		adj[ed.ff].push_back(ed.ss);
		adj[ed.ss].push_back(ed.ff);
	}
	int cur = n;
	while (true) {
		if (cur == 1) {
			for (int i = 1;i <= n;i++) {
				if (poss[i]) return i;
			}
			break;
		}
		for (int i = 1;i <= n;i++) found[i] = 0;
		que.clear();
		int num = cur / 2;
		cur -= num;
		dfs(1, 0, num);
		//cout << endl;
		int val = query(que);
		if (val) {
			for (int i = 1;i <= n;i++) {
				if (!found[i]) cost[i] = 0, poss[i] = 0;
			}
		} else {
			for (int i = 1;i <= n;i++) {
				if (found[i]) cost[i] = 0, poss[i] = 0;
			}
		}
	}
	return -1;
}
/*
5
1 2
1 3
2 4
3 5
5
1 2 3 4 5
 */

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