# | Time | Username | Problem | Language | Result | Execution time | Memory |
---|---|---|---|---|---|---|---|
918087 | Elvin_Fritl | Easter Eggs (info1cup17_eastereggs) | C++17 | 0 ms | 0 KiB |
This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include <bits/stdc++.h>
using namespace std;
#define ll long long
const int N=2e5+5, mod=1e9+7;
int n;
#include "grader.h"
vector<int> d , g[N];
void dfs(int s,int p) {
d.push_back(s);
for(auto i: g[s]) {
if(i == p) {
continue;
}
dfs(i,s);
}
}
int findEgg(int M , vector<pair<int , int>> &a) {
d.clear();
n = M;
for(int i=0;i<(int)a.size();i++) {
g[a[i].first].push_back(a[i].second);
g[a[i].second].push_back(a[i].first);
}
dfs(1 , 1);
int l = 1 , r = n , best = -1;
while(l <= r) {
int mid = (l + r)>>1;
vector<int> q;
for(int i=0;i<mid;i++) {
q.push_back(d[i]);
}
if(query(q) == 1) {
r = mid - 1;
best = mid;
}
else {
l = mid + 1;
}
}
return best;
}