# | Submission time | Handle | Problem | Language | Result | Execution time | Memory |
---|---|---|---|---|---|---|---|
475697 | 2021-09-23T17:11:51 Z | lovrot | Easter Eggs (info1cup17_eastereggs) | C++11 | 0 ms | 0 KB |
#include <bits/stdc++.h> #include <unordered_set> #include "grader.h" #define X first #define Y second using namespace std; vector<int> g[530]; vector<int> half; vector<int> all; vector<int> help; int have; bool took[530]; bool query(vector< int > half); void findHalf(int x){ if(have == 0) return; took[x] = true; half.push_back(x); have--; for(int y : g[x]){ if(took[y] == true) continue; findHalf(y); } } int findEgg (int n, vector< pair< int, int > > graf ){ memset(took, 0, sizeof(took)); for(int i = 0; i <= n; i++) g[i].clear(); for(int i = 0; i < n - 1; i++){ int x = graf[i].X; int y = graf[i].Y; g[x].push_back(y); g[y].push_back(x); if(!took[x]){ all.push_back(x); took[x] = true; } if(!took[y]){ all.push_back(y); took[y] = true; } } memset(took, false, sizeof(took)); while(all.size() > 1){ have = n / 2; half.clear(); findHalf(all[0]); bool ans = query(half); if(ans){ n /= 2; } else{ n = n - n / 2; } help.clear(); for(int x : all){ if(took[x] == ans) help.push_back(x); } all.clear(); for(int x : help){ took[x] = false; all.push_back(x); } } return all[0]; }