Submission #671474

#	Time	Username	Problem	Language	Result	Execution time	Memory
671474		loctildore	Easter Eggs (info1cup17_eastereggs)	C++14	100 / 100	21 ms	376 KiB

eastereggs

#include <bits/stdc++.h>
#include "grader.h"
#define f first
#define s second
using namespace std;
int n;
vector<int> preord;
vector<int> grph[690];
void dfs(int x, int lst=-1) {
	preord.push_back(x);
	for (int i : grph[x]) if (i!=lst) {
		dfs(i,x);
	}
}
bool test(int x) {
	vector<int> t;
	for (int i=0; i<x; i++) {
		t.push_back(preord[i]+1);
	}
	return query(t);
}
int findEgg (int N, vector<pair<int,int>> bridges) {
	preord.clear();
	for (int i=0; i<690; i++) {
		grph[i].clear();
	}
	n=N;
	for (auto i:bridges) {
		i.f--;i.s--;
		grph[i.f].push_back(i.s);
		grph[i.s].push_back(i.f);
	}
	dfs(0);
	int s=0,e=n;
	while(s+1!=e) {
		int m=(s+e)/2;
		(test(m)?e:s)=m;
	}
	return preord[s]+1;
}

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