Submission #61643

#	Time	Username	Problem	Language	Result	Execution time	Memory
61643		huynhsmd	Easter Eggs (info1cup17_eastereggs)	C++17	100 / 100	46 ms	3056 KiB

eastereggs

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

#define pb push_back
#define fi first
#define se second
using namespace std;

typedef pair <int , int > ii;
const int N = 1e5 + 5;
int arr[N], cnt = 0;
vector < int > adj[N], ask;

void dfs(int u, int p){
	arr[++cnt] = u;
	for(int v : adj[u]) if(v != p) dfs(v, u);
}
int findEgg(int N, vector < ii > bridges){
	int n = N;
	for(int i = 1; i <= n; ++ i) adj[i].clear();
	for(ii i : bridges) adj[i.fi].pb(i.se), adj[i.se].pb(i.fi);
	dfs(1, 1);
	int l = 1, r = n, res;
	while(l < r){
		int mid = l + r >> 1;
		ask.clear();
		for(int i = 1; i <= mid; ++ i) ask.pb(arr[i]);
		if(query(ask)) r = mid;
		else l = mid + 1;
	}
	return arr[l];
}

Compilation message (stderr)

eastereggs.cpp: In function 'int findEgg(int, std::vector<std::pair<int, int> >)':
eastereggs.cpp:25:15: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   int mid = l + r >> 1;
             ~~^~~
eastereggs.cpp:23:20: warning: unused variable 'res' [-Wunused-variable]
  int l = 1, r = n, res;
                    ^~~

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