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Submission #115949

# Submission time Handle Problem Language Result Execution time Memory
115949 2019-06-10T03:11:26 Z nhimnam120 Easter Eggs (info1cup17_eastereggs) C++14
100 / 100
 18 ms 384 KB 
#include <bits/stdc++.h>
#include "grader.h"
 
using namespace std;
 
vector<int> ask;
vector<int> adj[1005];
bool used[1005];
bool take[1005];
bool bad[1005];
int sz=0;
int cnt=0;
void dfs(int node, int fa)
{
	if(cnt==sz/2) return;
	if(used[node]==0)
	{
		cnt++;
	}
	ask.push_back(node);
	for(auto i:adj[node])
	{
		if(bad[i]!=0||i==fa) continue;
		dfs(i,node);
	}
}
 
int findEgg (int N, vector < pair < int, int > > bridges)
{
	ask.clear();
	memset(used, 0, sizeof(used));
	memset(bad, 0, sizeof(bad));
	for(int i=1; i<=N; i++)
	{
		adj[i].clear();
	}
	sz=N;
	for(auto i:bridges)
	{
		adj[i.first].push_back(i.second);
		adj[i.second].push_back(i.first);
	}
	while(true)
	{
		ask.clear();
		if(sz==1)
		{
			for(int i=1; i<=N; i++)
			{
				if(bad[i]==0&&used[i]==0)
				{
					return i;
				}
			}
		}
		else
		{
			cnt=0;
			dfs(1,1);
			if(query(ask)!=0)
			{
				sz=cnt;
				bool lay[1000];
				memset(lay, 0, sizeof(lay));
				for(auto i:ask)
				{
					lay[i]=1;
				}
				for(int i=1; i<=N; i++)
				{
					if(lay[i]==0)
					{
						bad[i]=true;
					}
				}
			}
			else
			{
				sz-=cnt;
				for(auto i:ask)
				{
					used[i]=true;
				}
			}
		}
	}
}

Subtask #1
40.0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 256 KB Number of queries: 4
2 Correct 2 ms 256 KB Number of queries: 4
3 Correct 3 ms 256 KB Number of queries: 4
4 Correct 2 ms 256 KB Number of queries: 4

Subtask #2
40.0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 5 ms 256 KB Number of queries: 8
2 Correct 10 ms 384 KB Number of queries: 9
3 Correct 17 ms 256 KB Number of queries: 9
4 Correct 17 ms 384 KB Number of queries: 9

Subtask #3
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 18 ms 384 KB Number of queries: 9
2 Correct 13 ms 256 KB Number of queries: 9
3 Correct 15 ms 256 KB Number of queries: 9
4 Correct 13 ms 256 KB Number of queries: 9