oj.uz

Submission #652109

# Submission time Handle Problem Language Result Execution time Memory
652109 2022-10-21T10:28:56 Z dooompy Network (BOI15_net) C++17
100 / 100
 483 ms 48152 KB 
#include "bits/stdc++.h"
 
using namespace std;
 
void abc() {cout << endl;}
template <typename T, typename ...U> void abc(T a, U ...b) {
    cout << a << ' ', abc(b...);
}
template <typename T> void printv(T l, T r) {
    while (l != r) cout << *l << " \n"[++l == r];
}
template <typename A, typename B> istream& operator >> (istream& o, pair<A, B> &a) {
    return o >> a.first >> a.second;
}
template <typename A, typename B> ostream& operator << (ostream& o, pair<A, B> a) {
    return o << '(' << a.first << ", " << a.second << ')';
}
template <typename T> ostream& operator << (ostream& o, vector<T> a) {
    bool is = false;
    for (T i : a) {o << (is ? ' ' : '{'), is = true, o << i;}
    return o << '}';
}
 
#ifdef local
#define test(args...) abc("[" + string(#args) + "]", args)
#else
#define test(args...) void(0)
#endif
 
using ll = long long;
 
vector<int> adj[500005];
bool seen[500005];
vector<int> order;
 
void dfs(int node) {
    seen[node] = true;
    bool leaf = true;
    for (auto nxt : adj[node]) {
        if (seen[nxt]) continue;
        dfs(nxt);
        leaf = false;
    }
    if (leaf) order.push_back(node);
}
 
int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);
//    freopen("", "r", stdin);
//    freopen("", "w", stdout);
    int n; cin >> n;
    for (int i = 0; i < n-1; i++) {
        int a, b; cin >>a >> b;
        adj[a].push_back(b);
        adj[b].push_back(a);
    }
 
    for (int i = 1; i <= n; i++) {
        if (adj[i].size() >= 2) {
            dfs(i);
            break;
        }
    }
 
    int s = order.size();
 
    cout << ceil(s / 2.0) << endl;
 
    for (int i = 0; i < (s + 1) /2; i++) {
        cout << order[i] << " " << order[min(i + s/2, s-1)] << "\n";
    }
}

Subtask #1
18.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 11988 KB Output is correct
2 Correct 7 ms 11988 KB Output is correct
3 Correct 6 ms 12064 KB Output is correct
4 Correct 7 ms 12048 KB Output is correct
5 Correct 7 ms 11988 KB Output is correct
6 Correct 7 ms 11988 KB Output is correct
7 Correct 6 ms 11988 KB Output is correct
8 Correct 6 ms 11988 KB Output is correct
9 Correct 6 ms 11988 KB Output is correct
10 Correct 7 ms 11988 KB Output is correct
11 Correct 6 ms 12068 KB Output is correct
12 Correct 7 ms 12072 KB Output is correct
13 Correct 7 ms 11952 KB Output is correct
14 Correct 6 ms 11988 KB Output is correct
15 Correct 7 ms 11988 KB Output is correct
16 Correct 7 ms 11988 KB Output is correct
17 Correct 7 ms 11988 KB Output is correct
18 Correct 7 ms 11948 KB Output is correct
19 Correct 7 ms 12068 KB Output is correct
20 Correct 6 ms 11988 KB Output is correct

Subtask #2
45.0 / 45.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 11988 KB Output is correct
2 Correct 7 ms 11988 KB Output is correct
3 Correct 6 ms 12064 KB Output is correct
4 Correct 7 ms 12048 KB Output is correct
5 Correct 7 ms 11988 KB Output is correct
6 Correct 7 ms 11988 KB Output is correct
7 Correct 6 ms 11988 KB Output is correct
8 Correct 6 ms 11988 KB Output is correct
9 Correct 6 ms 11988 KB Output is correct
10 Correct 7 ms 11988 KB Output is correct
11 Correct 6 ms 12068 KB Output is correct
12 Correct 7 ms 12072 KB Output is correct
13 Correct 7 ms 11952 KB Output is correct
14 Correct 6 ms 11988 KB Output is correct
15 Correct 7 ms 11988 KB Output is correct
16 Correct 7 ms 11988 KB Output is correct
17 Correct 7 ms 11988 KB Output is correct
18 Correct 7 ms 11948 KB Output is correct
19 Correct 7 ms 12068 KB Output is correct
20 Correct 6 ms 11988 KB Output is correct
21 Correct 7 ms 11988 KB Output is correct
22 Correct 7 ms 12116 KB Output is correct
23 Correct 9 ms 12116 KB Output is correct
24 Correct 7 ms 12116 KB Output is correct
25 Correct 7 ms 12116 KB Output is correct
26 Correct 7 ms 12080 KB Output is correct
27 Correct 9 ms 12208 KB Output is correct
28 Correct 8 ms 12120 KB Output is correct
29 Correct 7 ms 12116 KB Output is correct
30 Correct 7 ms 11988 KB Output is correct
31 Correct 8 ms 12116 KB Output is correct
32 Correct 7 ms 12068 KB Output is correct
33 Correct 7 ms 11988 KB Output is correct
34 Correct 7 ms 12072 KB Output is correct
35 Correct 6 ms 12072 KB Output is correct
36 Correct 7 ms 11988 KB Output is correct
37 Correct 7 ms 11988 KB Output is correct
38 Correct 7 ms 12116 KB Output is correct
39 Correct 7 ms 11988 KB Output is correct
40 Correct 7 ms 12064 KB Output is correct
41 Correct 7 ms 12068 KB Output is correct
42 Correct 7 ms 12068 KB Output is correct
43 Correct 7 ms 12116 KB Output is correct
44 Correct 6 ms 11988 KB Output is correct
45 Correct 6 ms 11988 KB Output is correct
46 Correct 8 ms 11988 KB Output is correct
47 Correct 7 ms 12072 KB Output is correct
48 Correct 7 ms 11988 KB Output is correct
49 Correct 7 ms 12036 KB Output is correct
50 Correct 7 ms 11988 KB Output is correct
51 Correct 7 ms 12064 KB Output is correct
52 Correct 7 ms 12068 KB Output is correct
53 Correct 7 ms 12084 KB Output is correct
54 Correct 6 ms 12072 KB Output is correct
55 Correct 6 ms 12064 KB Output is correct
56 Correct 7 ms 11988 KB Output is correct
57 Correct 7 ms 11988 KB Output is correct
58 Correct 7 ms 12132 KB Output is correct

Subtask #3
37.0 / 37.0

# Verdict Execution time Memory Grader output
1 Correct 6 ms 11988 KB Output is correct
2 Correct 7 ms 11988 KB Output is correct
3 Correct 6 ms 12064 KB Output is correct
4 Correct 7 ms 12048 KB Output is correct
5 Correct 7 ms 11988 KB Output is correct
6 Correct 7 ms 11988 KB Output is correct
7 Correct 6 ms 11988 KB Output is correct
8 Correct 6 ms 11988 KB Output is correct
9 Correct 6 ms 11988 KB Output is correct
10 Correct 7 ms 11988 KB Output is correct
11 Correct 6 ms 12068 KB Output is correct
12 Correct 7 ms 12072 KB Output is correct
13 Correct 7 ms 11952 KB Output is correct
14 Correct 6 ms 11988 KB Output is correct
15 Correct 7 ms 11988 KB Output is correct
16 Correct 7 ms 11988 KB Output is correct
17 Correct 7 ms 11988 KB Output is correct
18 Correct 7 ms 11948 KB Output is correct
19 Correct 7 ms 12068 KB Output is correct
20 Correct 6 ms 11988 KB Output is correct
21 Correct 7 ms 11988 KB Output is correct
22 Correct 7 ms 12116 KB Output is correct
23 Correct 9 ms 12116 KB Output is correct
24 Correct 7 ms 12116 KB Output is correct
25 Correct 7 ms 12116 KB Output is correct
26 Correct 7 ms 12080 KB Output is correct
27 Correct 9 ms 12208 KB Output is correct
28 Correct 8 ms 12120 KB Output is correct
29 Correct 7 ms 12116 KB Output is correct
30 Correct 7 ms 11988 KB Output is correct
31 Correct 8 ms 12116 KB Output is correct
32 Correct 7 ms 12068 KB Output is correct
33 Correct 7 ms 11988 KB Output is correct
34 Correct 7 ms 12072 KB Output is correct
35 Correct 6 ms 12072 KB Output is correct
36 Correct 7 ms 11988 KB Output is correct
37 Correct 7 ms 11988 KB Output is correct
38 Correct 7 ms 12116 KB Output is correct
39 Correct 7 ms 11988 KB Output is correct
40 Correct 7 ms 12064 KB Output is correct
41 Correct 7 ms 12068 KB Output is correct
42 Correct 7 ms 12068 KB Output is correct
43 Correct 7 ms 12116 KB Output is correct
44 Correct 6 ms 11988 KB Output is correct
45 Correct 6 ms 11988 KB Output is correct
46 Correct 8 ms 11988 KB Output is correct
47 Correct 7 ms 12072 KB Output is correct
48 Correct 7 ms 11988 KB Output is correct
49 Correct 7 ms 12036 KB Output is correct
50 Correct 7 ms 11988 KB Output is correct
51 Correct 7 ms 12064 KB Output is correct
52 Correct 7 ms 12068 KB Output is correct
53 Correct 7 ms 12084 KB Output is correct
54 Correct 6 ms 12072 KB Output is correct
55 Correct 6 ms 12064 KB Output is correct
56 Correct 7 ms 11988 KB Output is correct
57 Correct 7 ms 11988 KB Output is correct
58 Correct 7 ms 12132 KB Output is correct
59 Correct 298 ms 36404 KB Output is correct
60 Correct 355 ms 39288 KB Output is correct
61 Correct 7 ms 11988 KB Output is correct
62 Correct 7 ms 12072 KB Output is correct
63 Correct 254 ms 34040 KB Output is correct
64 Correct 8 ms 12500 KB Output is correct
65 Correct 15 ms 13868 KB Output is correct
66 Correct 118 ms 28068 KB Output is correct
67 Correct 422 ms 47436 KB Output is correct
68 Correct 419 ms 48152 KB Output is correct
69 Correct 12 ms 12884 KB Output is correct
70 Correct 68 ms 21440 KB Output is correct
71 Correct 243 ms 42372 KB Output is correct
72 Correct 255 ms 41196 KB Output is correct
73 Correct 81 ms 19148 KB Output is correct
74 Correct 367 ms 38268 KB Output is correct
75 Correct 25 ms 15316 KB Output is correct
76 Correct 253 ms 42140 KB Output is correct
77 Correct 321 ms 42120 KB Output is correct
78 Correct 34 ms 15536 KB Output is correct
79 Correct 483 ms 45564 KB Output is correct
80 Correct 8 ms 12276 KB Output is correct
81 Correct 79 ms 21456 KB Output is correct
82 Correct 307 ms 40000 KB Output is correct
83 Correct 364 ms 38288 KB Output is correct
84 Correct 382 ms 38168 KB Output is correct
85 Correct 382 ms 38196 KB Output is correct
86 Correct 368 ms 39184 KB Output is correct
87 Correct 364 ms 39260 KB Output is correct