Submission #946814

#	Time	Username	Problem	Language	Result	Execution time	Memory
946814		PenguinsAreCute	Easter Eggs (info1cup17_eastereggs)	C++17	100 / 100	13 ms	1252 KiB

eastereggs

#include <bits/stdc++.h>
#include "grader.h"
using namespace std;
int pre[569], c;
vector<int> adj[569];
void dfs(int x, int p) {
	pre[x] = c++;
	for(auto i: adj[x]) if(i!=p) dfs(i, x);
}
int findEgg (int N, vector < pair < int, int > > bridges) {
	for(int i=0;++i<=N;) adj[i].clear();
	for(auto [u, v]: bridges) {
		adj[u].push_back(v);
		adj[v].push_back(u);
	}
	c=0; dfs(1,-1);
	int l=-1, r=N-1;
	while(r-l>1) {
		int m=l+r>>1;
		vector<int> v;
		for(int i=0;++i<=N;) if(pre[i]<=m) v.push_back(i);
		if(query(v)) r=m;
		else l=m;
	}
	for(int i=0;++i<=N;) if(pre[i]==r) return i;
	cout << "Beware the Ides of March\n";
	return 69;
}

Compilation message (stderr)

eastereggs.cpp: In function 'int findEgg(int, std::vector<std::pair<int, int> >)':
eastereggs.cpp:19:10: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   19 |   int m=l+r>>1;
      |         ~^~

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