# | Time | Username | Problem | Language | Result | Execution time | Memory |
---|---|---|---|---|---|---|---|
410434 | nichke | Easter Eggs (info1cup17_eastereggs) | C++14 | 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;
vector<int> adj[513];
vector<int> euler;
set<int> pref[513];
vector<int> vi;
void dfs(int v, int p) {
euler.push_back(v);
for (int u : adj[v]) {
if (u == p) continue;
dfs(u, v);
euler.push_back(v);
}
}
int findEgg(int N, vector< pair <int, int> > bridges) {
for (int i = 0; i < 513; i++) {
adj[i].clear();
}
for (auto it : bridges) {
adj[it.first].push_back(it.second);
adj[it.second].push_back(it.first);
}
dfs(1, 1);
pref[0].insert(euler[0]);
for (int i = 1; i < euler.size(); i++) {
pref[i] = pref[i - 1];
pref[i].insert(euler[i]);
}
int l = 0, r = euler.size() - 1;
int flag = -1;
while (l <= r) {
vi.clear();
int m = (l + r) / 2;
for (int i : pref[m]) {
vi.push_back(i);
}
int k = query(vi);
if (k) {
flag = m;
r = m - 1;
} else {
l = m + 1;
}
}
if (flag) {
for (int i : pref[flag - 1]) {
pref[flag].erase(i);
}
}
for (int i : pref[flag]) {
return i;
}
}