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Submission #96093

# Submission time Handle Problem Language Result Execution time Memory
96093 2019-02-05T19:20:53 Z andrei110901 Network (BOI15_net) C++14
100 / 100
 1046 ms 92636 KB 
#include <bits/stdc++.h>

using namespace std;

vector <vector <int>> ad, gramezi;
vector <int> sub;
int nrf, cf;

void dfs(int nod, int par){
    if(ad[nod].size() == 1)
        sub[nod] = 1;
    for(auto fiu : ad[nod])
        if(fiu != par){
            dfs(fiu, nod);
            sub[nod] += sub[fiu];
        }
}

int get_centroid(int nod, int par){
    for(auto fiu : ad[nod])
        if(fiu != par && sub[fiu] > nrf / 2)
            return get_centroid(fiu, nod);
    return nod;
}

struct cmp{
    bool operator()(const int &lhs, const int &rhs){
        if(gramezi[lhs].size() == gramezi[rhs].size())
            return lhs < rhs;
        return gramezi[lhs].size() > gramezi[rhs].size();
    }
};


void Frunza(int nod, int par, vector <int> &v){
    if(ad[nod].size() == 1){
        v.push_back(nod);
        return;
    }
    for(auto fiu : ad[nod])
        if(fiu != par)
            Frunza(fiu, nod, v);
}

int main()
{
    int n, x, y;
    //ios::sync_with_stdio(false);
    cin >> n;
    nrf = n;
    ad.resize(n + 1);
    sub.resize(n + 1);
    for(int i = 1; i < n; i++){
        cin >> x >> y;
        ad[x].push_back(y);
        ad[y].push_back(x);
    }
    dfs(1, 0);
    nrf = sub[1];
    cf = get_centroid(1, 0);
    set <int, cmp> q;
    for(auto fiu : ad[cf]){
        vector <int> v;
        Frunza(fiu, cf, v);
        gramezi.push_back(v);
    }
    for(int i = 0; i < gramezi.size(); i++)
        q.insert(i);
    cout << (nrf + 1) / 2 << '\n';
    if(nrf % 2 == 1){
        int aux = *q.begin();
        q.erase(q.begin());
        cout << cf << ' ' << gramezi[aux].back() << '\n';
        gramezi[aux].pop_back();
        q.insert(aux);
    }
    while(gramezi[*(q.begin())].size() > 0){
        int i1 = *(q.begin());
        q.erase(q.begin());
        int i2 = *(q.begin());
        q.erase(q.begin());
        cout << gramezi[i1].back() << ' ' << gramezi[i2].back() << '\n';
        gramezi[i1].pop_back();
        gramezi[i2].pop_back();
        q.insert(i1);
        q.insert(i2);
    }
    return 0;
}

Compilation message

net.cpp: In function 'int main()':
net.cpp:67:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i = 0; i < gramezi.size(); i++)
                    ~~^~~~~~~~~~~~~~~~

Subtask #1
18.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 256 KB Output is correct
2 Correct 2 ms 376 KB Output is correct
3 Correct 2 ms 376 KB Output is correct
4 Correct 2 ms 256 KB Output is correct
5 Correct 2 ms 256 KB Output is correct
6 Correct 2 ms 376 KB Output is correct
7 Correct 2 ms 376 KB Output is correct
8 Correct 2 ms 252 KB Output is correct
9 Correct 2 ms 256 KB Output is correct
10 Correct 2 ms 376 KB Output is correct
11 Correct 2 ms 256 KB Output is correct
12 Correct 2 ms 252 KB Output is correct
13 Correct 2 ms 444 KB Output is correct
14 Correct 2 ms 256 KB Output is correct
15 Correct 2 ms 256 KB Output is correct
16 Correct 2 ms 292 KB Output is correct
17 Correct 2 ms 348 KB Output is correct
18 Correct 2 ms 256 KB Output is correct
19 Correct 2 ms 256 KB Output is correct
20 Correct 2 ms 252 KB Output is correct

Subtask #2
45.0 / 45.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 256 KB Output is correct
2 Correct 2 ms 376 KB Output is correct
3 Correct 2 ms 376 KB Output is correct
4 Correct 2 ms 256 KB Output is correct
5 Correct 2 ms 256 KB Output is correct
6 Correct 2 ms 376 KB Output is correct
7 Correct 2 ms 376 KB Output is correct
8 Correct 2 ms 252 KB Output is correct
9 Correct 2 ms 256 KB Output is correct
10 Correct 2 ms 376 KB Output is correct
11 Correct 2 ms 256 KB Output is correct
12 Correct 2 ms 252 KB Output is correct
13 Correct 2 ms 444 KB Output is correct
14 Correct 2 ms 256 KB Output is correct
15 Correct 2 ms 256 KB Output is correct
16 Correct 2 ms 292 KB Output is correct
17 Correct 2 ms 348 KB Output is correct
18 Correct 2 ms 256 KB Output is correct
19 Correct 2 ms 256 KB Output is correct
20 Correct 2 ms 252 KB Output is correct
21 Correct 2 ms 280 KB Output is correct
22 Correct 4 ms 504 KB Output is correct
23 Correct 4 ms 508 KB Output is correct
24 Correct 4 ms 632 KB Output is correct
25 Correct 4 ms 504 KB Output is correct
26 Correct 4 ms 504 KB Output is correct
27 Correct 4 ms 504 KB Output is correct
28 Correct 4 ms 376 KB Output is correct
29 Correct 3 ms 376 KB Output is correct
30 Correct 2 ms 256 KB Output is correct
31 Correct 3 ms 376 KB Output is correct
32 Correct 2 ms 256 KB Output is correct
33 Correct 2 ms 256 KB Output is correct
34 Correct 2 ms 256 KB Output is correct
35 Correct 2 ms 376 KB Output is correct
36 Correct 2 ms 256 KB Output is correct
37 Correct 2 ms 420 KB Output is correct
38 Correct 3 ms 376 KB Output is correct
39 Correct 2 ms 256 KB Output is correct
40 Correct 2 ms 256 KB Output is correct
41 Correct 2 ms 376 KB Output is correct
42 Correct 3 ms 376 KB Output is correct
43 Correct 3 ms 504 KB Output is correct
44 Correct 2 ms 256 KB Output is correct
45 Correct 2 ms 376 KB Output is correct
46 Correct 2 ms 380 KB Output is correct
47 Correct 2 ms 252 KB Output is correct
48 Correct 2 ms 404 KB Output is correct
49 Correct 3 ms 376 KB Output is correct
50 Correct 2 ms 376 KB Output is correct
51 Correct 2 ms 376 KB Output is correct
52 Correct 3 ms 376 KB Output is correct
53 Correct 3 ms 376 KB Output is correct
54 Correct 2 ms 376 KB Output is correct
55 Correct 3 ms 376 KB Output is correct
56 Correct 2 ms 376 KB Output is correct
57 Correct 2 ms 376 KB Output is correct
58 Correct 3 ms 504 KB Output is correct

Subtask #3
37.0 / 37.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 256 KB Output is correct
2 Correct 2 ms 376 KB Output is correct
3 Correct 2 ms 376 KB Output is correct
4 Correct 2 ms 256 KB Output is correct
5 Correct 2 ms 256 KB Output is correct
6 Correct 2 ms 376 KB Output is correct
7 Correct 2 ms 376 KB Output is correct
8 Correct 2 ms 252 KB Output is correct
9 Correct 2 ms 256 KB Output is correct
10 Correct 2 ms 376 KB Output is correct
11 Correct 2 ms 256 KB Output is correct
12 Correct 2 ms 252 KB Output is correct
13 Correct 2 ms 444 KB Output is correct
14 Correct 2 ms 256 KB Output is correct
15 Correct 2 ms 256 KB Output is correct
16 Correct 2 ms 292 KB Output is correct
17 Correct 2 ms 348 KB Output is correct
18 Correct 2 ms 256 KB Output is correct
19 Correct 2 ms 256 KB Output is correct
20 Correct 2 ms 252 KB Output is correct
21 Correct 2 ms 280 KB Output is correct
22 Correct 4 ms 504 KB Output is correct
23 Correct 4 ms 508 KB Output is correct
24 Correct 4 ms 632 KB Output is correct
25 Correct 4 ms 504 KB Output is correct
26 Correct 4 ms 504 KB Output is correct
27 Correct 4 ms 504 KB Output is correct
28 Correct 4 ms 376 KB Output is correct
29 Correct 3 ms 376 KB Output is correct
30 Correct 2 ms 256 KB Output is correct
31 Correct 3 ms 376 KB Output is correct
32 Correct 2 ms 256 KB Output is correct
33 Correct 2 ms 256 KB Output is correct
34 Correct 2 ms 256 KB Output is correct
35 Correct 2 ms 376 KB Output is correct
36 Correct 2 ms 256 KB Output is correct
37 Correct 2 ms 420 KB Output is correct
38 Correct 3 ms 376 KB Output is correct
39 Correct 2 ms 256 KB Output is correct
40 Correct 2 ms 256 KB Output is correct
41 Correct 2 ms 376 KB Output is correct
42 Correct 3 ms 376 KB Output is correct
43 Correct 3 ms 504 KB Output is correct
44 Correct 2 ms 256 KB Output is correct
45 Correct 2 ms 376 KB Output is correct
46 Correct 2 ms 380 KB Output is correct
47 Correct 2 ms 252 KB Output is correct
48 Correct 2 ms 404 KB Output is correct
49 Correct 3 ms 376 KB Output is correct
50 Correct 2 ms 376 KB Output is correct
51 Correct 2 ms 376 KB Output is correct
52 Correct 3 ms 376 KB Output is correct
53 Correct 3 ms 376 KB Output is correct
54 Correct 2 ms 376 KB Output is correct
55 Correct 3 ms 376 KB Output is correct
56 Correct 2 ms 376 KB Output is correct
57 Correct 2 ms 376 KB Output is correct
58 Correct 3 ms 504 KB Output is correct
59 Correct 837 ms 44972 KB Output is correct
60 Correct 851 ms 40792 KB Output is correct
61 Correct 2 ms 256 KB Output is correct
62 Correct 2 ms 256 KB Output is correct
63 Correct 787 ms 41680 KB Output is correct
64 Correct 6 ms 888 KB Output is correct
65 Correct 25 ms 3064 KB Output is correct
66 Correct 307 ms 23716 KB Output is correct
67 Correct 1046 ms 53016 KB Output is correct
68 Correct 1024 ms 54028 KB Output is correct
69 Correct 22 ms 2996 KB Output is correct
70 Correct 261 ms 27476 KB Output is correct
71 Correct 985 ms 92636 KB Output is correct
72 Correct 950 ms 86296 KB Output is correct
73 Correct 174 ms 11132 KB Output is correct
74 Correct 812 ms 40000 KB Output is correct
75 Correct 71 ms 7476 KB Output is correct
76 Correct 852 ms 66896 KB Output is correct
77 Correct 857 ms 68196 KB Output is correct
78 Correct 56 ms 5368 KB Output is correct
79 Correct 1022 ms 50860 KB Output is correct
80 Correct 6 ms 760 KB Output is correct
81 Correct 277 ms 22268 KB Output is correct
82 Correct 904 ms 65884 KB Output is correct
83 Correct 867 ms 40100 KB Output is correct
84 Correct 761 ms 39944 KB Output is correct
85 Correct 900 ms 40144 KB Output is correct
86 Correct 861 ms 40752 KB Output is correct
87 Correct 805 ms 40876 KB Output is correct