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Submission #102145

# Submission time Handle Problem Language Result Execution time Memory
102145 2019-03-22T20:07:51 Z Leonardo_Paes Network (BOI15_net) C++11
0 / 100
 3 ms 384 KB 
#include <bits/stdc++.h>

using namespace std;

const int MAXN = 5e5 + 100;

int grau[MAXN];

int main(){

    int n;

    cin >> n;

    for(int i=1; i<n; i++){
        int a, b;

        cin >> a >> b;

        grau[a]++;
        grau[b]++;
    }

    vector<int> v;

    for(int i=1; i<=n; i++){
        if(grau[i]==1){
            v.push_back(i);
        }
    }

    int ans = (v.size()+1)/2;

    cout << ans << "\n";

    for(int i=0; i<ans-1; i++){
        cout << v[i] << " " << v[i+ans] << "\n";
    }
    if(v.size()&1){
        cout << v[ans-1] << " " << v[0] << "\n";
    }
    else{
        cout << v[ans-1] << " " << v[v.size()-1];
    }
    return 0;
}

Subtask #1
0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 256 KB Output is correct
2 Correct 2 ms 256 KB Output is correct
3 Correct 2 ms 384 KB Output is correct
4 Correct 2 ms 256 KB Output is correct
5 Correct 3 ms 384 KB Output is correct
6 Correct 2 ms 384 KB Output is correct
7 Correct 2 ms 256 KB Output is correct
8 Correct 2 ms 256 KB Output is correct
9 Correct 2 ms 256 KB Output is correct
10 Correct 2 ms 256 KB Output is correct
11 Correct 3 ms 384 KB Output is correct
12 Incorrect 2 ms 384 KB Breaking single line is causing network to disconnect.
13 Halted 0 ms 0 KB -

Subtask #2
0 / 45.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 256 KB Output is correct
2 Correct 2 ms 256 KB Output is correct
3 Correct 2 ms 384 KB Output is correct
4 Correct 2 ms 256 KB Output is correct
5 Correct 3 ms 384 KB Output is correct
6 Correct 2 ms 384 KB Output is correct
7 Correct 2 ms 256 KB Output is correct
8 Correct 2 ms 256 KB Output is correct
9 Correct 2 ms 256 KB Output is correct
10 Correct 2 ms 256 KB Output is correct
11 Correct 3 ms 384 KB Output is correct
12 Incorrect 2 ms 384 KB Breaking single line is causing network to disconnect.
13 Halted 0 ms 0 KB -

Subtask #3
0 / 37.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 256 KB Output is correct
2 Correct 2 ms 256 KB Output is correct
3 Correct 2 ms 384 KB Output is correct
4 Correct 2 ms 256 KB Output is correct
5 Correct 3 ms 384 KB Output is correct
6 Correct 2 ms 384 KB Output is correct
7 Correct 2 ms 256 KB Output is correct
8 Correct 2 ms 256 KB Output is correct
9 Correct 2 ms 256 KB Output is correct
10 Correct 2 ms 256 KB Output is correct
11 Correct 3 ms 384 KB Output is correct
12 Incorrect 2 ms 384 KB Breaking single line is causing network to disconnect.
13 Halted 0 ms 0 KB -