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Submission #521063

# Submission time Handle Problem Language Result Execution time Memory
521063 2022-01-31T16:59:43 Z Jomnoi Easter Eggs (info1cup17_eastereggs) C++17
100 / 100
 18 ms 464 KB 
#include <bits/stdc++.h>
#include "grader.h"
#define DEBUG 0
using namespace std;

const int MAX = 520;

int timer;
vector <int> adj[MAX];
int st[MAX];

void dfs(int u, int p) {
    st[++timer] = u;
    for(auto v : adj[u]) {
        if(v != p) {
            dfs(v, u);
        }
    }
}

int findEgg(int N, vector <pair <int, int>> bridges) {
    timer = 0;
    for(int i = 1; i <= N; i++) {
        adj[i].clear();
    }

    for(auto [u, v] : bridges) {
        adj[u].push_back(v);
        adj[v].push_back(u);
    }

    dfs(1, -1);

    int l = 1, r = N;
    while(l < r) {
        int mid = (l + r) / 2;

        vector <int> islands;
        for(int i = 1; i <= mid; i++) {
            islands.push_back(st[i]);
        }

        if(query(islands) == 1) {
            r = mid;
        }
        else {
            l = mid + 1;
        }
    }
    return st[l];
}

Subtask #1
40.0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 200 KB Number of queries: 4
2 Correct 1 ms 200 KB Number of queries: 4
3 Correct 1 ms 200 KB Number of queries: 4
4 Correct 1 ms 200 KB Number of queries: 4

Subtask #2
40.0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 328 KB Number of queries: 8
2 Correct 12 ms 352 KB Number of queries: 9
3 Correct 16 ms 328 KB Number of queries: 9
4 Correct 16 ms 344 KB Number of queries: 9

Subtask #3
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 17 ms 344 KB Number of queries: 9
2 Correct 14 ms 328 KB Number of queries: 9
3 Correct 17 ms 352 KB Number of queries: 9
4 Correct 18 ms 464 KB Number of queries: 9