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Submission #49404

# Submission time Handle Problem Language Result Execution time Memory
49404 2018-05-28T10:31:41 Z georgerapeanu Easter Eggs (info1cup17_eastereggs) C++11
100 / 100
 28 ms 700 KB 
#include <bits/stdc++.h>
#include "grader.h"

using namespace std;

vector<int> G[600];
int renumbered[600];
int inverse_renumber[600];


void renumber_dfs(int node,int father,int &val){
    renumbered[node] = val;
    inverse_renumber[val] = node;
    for(auto it:G[node]){
        if(it != father){
            renumber_dfs(it,node,++val);
        }
    }
}

vector<int> nodes;
bool ok(int le,int ri){
    nodes.clear();
    for(int i = le;i <= ri;i++){
        nodes.push_back(inverse_renumber[i]);
    }
    return query(nodes);
}

int findEgg (int N, vector < pair < int, int > > bridges){
    for(int i = 1;i <= N;i++){
        G[i].clear();
    }
    for(auto it:bridges){
        G[it.first].push_back(it.second);
        G[it.second].push_back(it.first);
    }
    int start = 1;
    renumber_dfs(1,0,start);


    int lo = 1,hi = N;
    while(hi - lo > 0){
        int mid = (lo + hi) / 2;
        if(ok(1,mid)){
            hi = mid;
        }
        else{
            lo = mid + 1;
        }
    }
    return inverse_renumber[lo];
}

Subtask #1
40.0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 248 KB Number of queries: 4
2 Correct 4 ms 308 KB Number of queries: 4
3 Correct 3 ms 472 KB Number of queries: 4
4 Correct 2 ms 472 KB Number of queries: 4

Subtask #2
40.0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 548 KB Number of queries: 8
2 Correct 14 ms 548 KB Number of queries: 9
3 Correct 24 ms 548 KB Number of queries: 9
4 Correct 27 ms 548 KB Number of queries: 9

Subtask #3
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 21 ms 568 KB Number of queries: 9
2 Correct 28 ms 572 KB Number of queries: 9
3 Correct 23 ms 576 KB Number of queries: 9
4 Correct 19 ms 700 KB Number of queries: 9