Submission #1319368

#	Time	Username	Problem	Language	Result	Execution time	Memory
1319368		sashimivssushi	Easter Eggs (info1cup17_eastereggs)	C++20	100 / 100	9 ms	480 KiB

eastereggs

#include <bits/stdc++.h>
#include "grader.h"
#define vt vector
#define pii pair<int, int>
#define fi first
#define sc second

using namespace std;

int findEgg (int n, vt<pii> edges) {
    vt<int> path(n + 1);
    vt<vt<int>> adj(n + 1);
    int timeDFS = 0;
    for (auto& edge : edges) {
        adj[edge.fi].emplace_back(edge.sc);
        adj[edge.sc].emplace_back(edge.fi);
    }
    auto dfs = [&] (auto& dfs, int u, int p) -> void {
        path[++timeDFS] = u;
        for (int& v : adj[u]) {
            if (v != p) dfs(dfs, v, u);
        }
    };
    dfs(dfs, 1, 1);
    int lo = 1, hi = n;
    while (lo < hi) {
        int mid = (lo + hi) >> 1;
        vt<int> v;
        for (int i = 1; i <= mid; ++i)
            v.emplace_back(path[i]);
        if (query(v)) hi = mid;
        else lo = mid + 1;
    }
    return path[lo];
}

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