Submission #571360

#	Time	Username	Problem	Language	Result	Execution time	Memory
571360		Deepesson	Easter Eggs (info1cup17_eastereggs)	C++17	100 / 100	46 ms	464 KiB

eastereggs

#include<bits/stdc++.h>
#include "grader.h"
#define MAX 600
using namespace std;
int findEgg(int N, vector < pair < int, int > > bridges);
int query(vector < int > islands);

std::vector<int> con[MAX];
std::map<int,bool> candidatos;

std::vector<int> buscar;
int counta=0,obj;
void dfs(int pos,int prev){
   // std::cout<<"Explora "<<pos<<" "<<prev<<" "<<obj<<"\n";
    buscar.push_back(pos);
    if(candidatos.find(pos)!=candidatos.end()){
        ++counta;
    }
    if(counta==obj)return;
    for(auto&x:con[pos]){
        if(x==prev)continue;
        if(counta==obj)return;
        dfs(x,pos);
    }
}
int findEgg (int N, vector < pair < int, int > > bridges)
{
    for(int i=0;i!=N+20;++i)con[i].clear();
   // std::cout<<"Lesgo\n";
    for(int i=1;i!=N+1;++i){
        candidatos[i]=1;
        if(i!=1){
          //  std::cout<<bridges[i-2].first<<" "<<bridges[i-2].second<<"\n";
            con[bridges[i-2].first].push_back(bridges[i-2].second);
            con[bridges[i-2].second].push_back(bridges[i-2].first);
        }
    }
   // std::cout<<"key\n";
    while(candidatos.size()!=1){
        obj=candidatos.size()/2;
        buscar.clear();counta=0;
        dfs(1,-1);
       // std::cout<<"busca "<<buscar.size()<<"\n";
        //for(auto&x:buscar)std::cout<<x<<" ";std::cout<<"\n";
        bool val = query(buscar);
        if(!val){
            for(auto&x:buscar){
                auto tem = candidatos.find(x);
                if(tem!=candidatos.end())candidatos.erase(tem);
            }
        }else {
            std::map<int,bool> obrigatorio;
            for(auto&x:buscar)obrigatorio[x]=true;
            std::vector<int> fora;
            for(auto&x:candidatos)if(!obrigatorio[x.first])fora.push_back(x.first);
            for(auto&x:fora){
                auto tem = candidatos.find(x);
                if(tem!=candidatos.end())candidatos.erase(tem);
            }
        }
    }
    int val;
    for(auto&x:candidatos)val=x.first;
    return val;
}

Compilation message (stderr)

eastereggs.cpp: In function 'int findEgg(int, std::vector<std::pair<int, int> >)':
eastereggs.cpp:64:12: warning: 'val' may be used uninitialized in this function [-Wmaybe-uninitialized]
   64 |     return val;
      |            ^~~

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