oj.uz

Submission #710863

# Submission time Handle Problem Language Result Execution time Memory
710863 2023-03-16T03:00:14 Z Charizard2021 Network (BOI15_net) C++17
100 / 100
 761 ms 66616 KB 
#include<bits/stdc++.h>
using namespace std;
const int N = 500001;
bool visited[N];
int LeavesInsubtee[N];
vector<int> adj[N];
vector<int> res[N];
int n;
int ans = 0;
int cur_ans = 0;
int subtreeValue = 0;
void dfs(int u){
    visited[u] = true;
    if((int)adj[u].size() == 1){
        LeavesInsubtee[u] = 1;
    }
    for(int v : adj[u]){
        if(!visited[v]){
            dfs(v);
            LeavesInsubtee[u] += LeavesInsubtee[v];
        }
    }
}
void dfs2(int u){
    visited[u] = true;
    if((int)adj[u].size() == 1){
        res[subtreeValue].push_back(u);
    }
    for(int v : adj[u]){
        if(!visited[v]){
            dfs2(v);
        }
    }
}
int cutlocation(int u){
    visited[u] = true;
    for(int v : adj[u]){
        if(!visited[v]){
            if(LeavesInsubtee[v] > floor((cur_ans)/2)){
                return cutlocation(v);
            }
        }
    }
    return u;
}
int cut(int u){
    dfs(1);
    for(int i = 1; i <= n; i++){
        visited[i] = false;
    }
    int x = cutlocation(1);
    for(int i = 1; i <= n; i++){
        visited[i] = false;
    }
    visited[x] = true;
    for(int v : adj[x]){
        subtreeValue++;
        dfs2(v);
    }
    return x;
}
int main(){
    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((int)adj[i].size() == 1){
            ans++;
        }
    }
    cur_ans = ans;
    ans = (ans + 1)/2;
    cout << ans << "\n";
    cut(n);
    vector<int> finalAns(2 * ans);
    int idx = 0;
    for(int i = 1; i <= subtreeValue; i++){
        for(int j = 0; j < (int)res[i].size(); j++){
            finalAns[idx] = res[i][j];
            idx += 2;
            if(idx == 2 * ans){
                idx = 1;
            }
        }
    }
    if(!(finalAns.empty()) && finalAns.back() == 0){
        finalAns.back() = res[1][0];
    }
    for(int i = 0; i < (int)finalAns.size(); i += 2){
        cout << finalAns[i] << " " << finalAns[i + 1] << "\n";
    }
}

Subtask #1
18.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 12 ms 23764 KB Output is correct
2 Correct 11 ms 23696 KB Output is correct
3 Correct 11 ms 23764 KB Output is correct
4 Correct 13 ms 23728 KB Output is correct
5 Correct 12 ms 23764 KB Output is correct
6 Correct 12 ms 23764 KB Output is correct
7 Correct 11 ms 23764 KB Output is correct
8 Correct 12 ms 23764 KB Output is correct
9 Correct 12 ms 23788 KB Output is correct
10 Correct 13 ms 23796 KB Output is correct
11 Correct 12 ms 23764 KB Output is correct
12 Correct 13 ms 23672 KB Output is correct
13 Correct 13 ms 23764 KB Output is correct
14 Correct 12 ms 23764 KB Output is correct
15 Correct 12 ms 23700 KB Output is correct
16 Correct 12 ms 23796 KB Output is correct
17 Correct 13 ms 23764 KB Output is correct
18 Correct 13 ms 23764 KB Output is correct
19 Correct 15 ms 23792 KB Output is correct
20 Correct 13 ms 23764 KB Output is correct

Subtask #2
45.0 / 45.0

# Verdict Execution time Memory Grader output
1 Correct 12 ms 23764 KB Output is correct
2 Correct 11 ms 23696 KB Output is correct
3 Correct 11 ms 23764 KB Output is correct
4 Correct 13 ms 23728 KB Output is correct
5 Correct 12 ms 23764 KB Output is correct
6 Correct 12 ms 23764 KB Output is correct
7 Correct 11 ms 23764 KB Output is correct
8 Correct 12 ms 23764 KB Output is correct
9 Correct 12 ms 23788 KB Output is correct
10 Correct 13 ms 23796 KB Output is correct
11 Correct 12 ms 23764 KB Output is correct
12 Correct 13 ms 23672 KB Output is correct
13 Correct 13 ms 23764 KB Output is correct
14 Correct 12 ms 23764 KB Output is correct
15 Correct 12 ms 23700 KB Output is correct
16 Correct 12 ms 23796 KB Output is correct
17 Correct 13 ms 23764 KB Output is correct
18 Correct 13 ms 23764 KB Output is correct
19 Correct 15 ms 23792 KB Output is correct
20 Correct 13 ms 23764 KB Output is correct
21 Correct 13 ms 23792 KB Output is correct
22 Correct 15 ms 23924 KB Output is correct
23 Correct 14 ms 23892 KB Output is correct
24 Correct 15 ms 23908 KB Output is correct
25 Correct 15 ms 23908 KB Output is correct
26 Correct 15 ms 23892 KB Output is correct
27 Correct 14 ms 23848 KB Output is correct
28 Correct 14 ms 23800 KB Output is correct
29 Correct 14 ms 23792 KB Output is correct
30 Correct 14 ms 23688 KB Output is correct
31 Correct 14 ms 23892 KB Output is correct
32 Correct 13 ms 23764 KB Output is correct
33 Correct 12 ms 23788 KB Output is correct
34 Correct 12 ms 23764 KB Output is correct
35 Correct 13 ms 23708 KB Output is correct
36 Correct 12 ms 23792 KB Output is correct
37 Correct 13 ms 23764 KB Output is correct
38 Correct 12 ms 23796 KB Output is correct
39 Correct 12 ms 23764 KB Output is correct
40 Correct 12 ms 23764 KB Output is correct
41 Correct 14 ms 23764 KB Output is correct
42 Correct 12 ms 23792 KB Output is correct
43 Correct 12 ms 23792 KB Output is correct
44 Correct 12 ms 23764 KB Output is correct
45 Correct 12 ms 23764 KB Output is correct
46 Correct 15 ms 23796 KB Output is correct
47 Correct 12 ms 23756 KB Output is correct
48 Correct 13 ms 23764 KB Output is correct
49 Correct 13 ms 23764 KB Output is correct
50 Correct 12 ms 23764 KB Output is correct
51 Correct 13 ms 23764 KB Output is correct
52 Correct 12 ms 23792 KB Output is correct
53 Correct 13 ms 23732 KB Output is correct
54 Correct 12 ms 23764 KB Output is correct
55 Correct 13 ms 23764 KB Output is correct
56 Correct 13 ms 23704 KB Output is correct
57 Correct 13 ms 23764 KB Output is correct
58 Correct 14 ms 23880 KB Output is correct

Subtask #3
37.0 / 37.0

# Verdict Execution time Memory Grader output
1 Correct 12 ms 23764 KB Output is correct
2 Correct 11 ms 23696 KB Output is correct
3 Correct 11 ms 23764 KB Output is correct
4 Correct 13 ms 23728 KB Output is correct
5 Correct 12 ms 23764 KB Output is correct
6 Correct 12 ms 23764 KB Output is correct
7 Correct 11 ms 23764 KB Output is correct
8 Correct 12 ms 23764 KB Output is correct
9 Correct 12 ms 23788 KB Output is correct
10 Correct 13 ms 23796 KB Output is correct
11 Correct 12 ms 23764 KB Output is correct
12 Correct 13 ms 23672 KB Output is correct
13 Correct 13 ms 23764 KB Output is correct
14 Correct 12 ms 23764 KB Output is correct
15 Correct 12 ms 23700 KB Output is correct
16 Correct 12 ms 23796 KB Output is correct
17 Correct 13 ms 23764 KB Output is correct
18 Correct 13 ms 23764 KB Output is correct
19 Correct 15 ms 23792 KB Output is correct
20 Correct 13 ms 23764 KB Output is correct
21 Correct 13 ms 23792 KB Output is correct
22 Correct 15 ms 23924 KB Output is correct
23 Correct 14 ms 23892 KB Output is correct
24 Correct 15 ms 23908 KB Output is correct
25 Correct 15 ms 23908 KB Output is correct
26 Correct 15 ms 23892 KB Output is correct
27 Correct 14 ms 23848 KB Output is correct
28 Correct 14 ms 23800 KB Output is correct
29 Correct 14 ms 23792 KB Output is correct
30 Correct 14 ms 23688 KB Output is correct
31 Correct 14 ms 23892 KB Output is correct
32 Correct 13 ms 23764 KB Output is correct
33 Correct 12 ms 23788 KB Output is correct
34 Correct 12 ms 23764 KB Output is correct
35 Correct 13 ms 23708 KB Output is correct
36 Correct 12 ms 23792 KB Output is correct
37 Correct 13 ms 23764 KB Output is correct
38 Correct 12 ms 23796 KB Output is correct
39 Correct 12 ms 23764 KB Output is correct
40 Correct 12 ms 23764 KB Output is correct
41 Correct 14 ms 23764 KB Output is correct
42 Correct 12 ms 23792 KB Output is correct
43 Correct 12 ms 23792 KB Output is correct
44 Correct 12 ms 23764 KB Output is correct
45 Correct 12 ms 23764 KB Output is correct
46 Correct 15 ms 23796 KB Output is correct
47 Correct 12 ms 23756 KB Output is correct
48 Correct 13 ms 23764 KB Output is correct
49 Correct 13 ms 23764 KB Output is correct
50 Correct 12 ms 23764 KB Output is correct
51 Correct 13 ms 23764 KB Output is correct
52 Correct 12 ms 23792 KB Output is correct
53 Correct 13 ms 23732 KB Output is correct
54 Correct 12 ms 23764 KB Output is correct
55 Correct 13 ms 23764 KB Output is correct
56 Correct 13 ms 23704 KB Output is correct
57 Correct 13 ms 23764 KB Output is correct
58 Correct 14 ms 23880 KB Output is correct
59 Correct 582 ms 50572 KB Output is correct
60 Correct 652 ms 49604 KB Output is correct
61 Correct 13 ms 23712 KB Output is correct
62 Correct 13 ms 23764 KB Output is correct
63 Correct 498 ms 46672 KB Output is correct
64 Correct 15 ms 24296 KB Output is correct
65 Correct 31 ms 25996 KB Output is correct
66 Correct 226 ms 42304 KB Output is correct
67 Correct 751 ms 60424 KB Output is correct
68 Correct 734 ms 61532 KB Output is correct
69 Correct 24 ms 25228 KB Output is correct
70 Correct 156 ms 37280 KB Output is correct
71 Correct 556 ms 66616 KB Output is correct
72 Correct 644 ms 64112 KB Output is correct
73 Correct 135 ms 31504 KB Output is correct
74 Correct 668 ms 47972 KB Output is correct
75 Correct 55 ms 28040 KB Output is correct
76 Correct 521 ms 59060 KB Output is correct
77 Correct 525 ms 59776 KB Output is correct
78 Correct 61 ms 27544 KB Output is correct
79 Correct 761 ms 58456 KB Output is correct
80 Correct 15 ms 24020 KB Output is correct
81 Correct 205 ms 35924 KB Output is correct
82 Correct 604 ms 57404 KB Output is correct
83 Correct 655 ms 48284 KB Output is correct
84 Correct 648 ms 48508 KB Output is correct
85 Correct 656 ms 48664 KB Output is correct
86 Correct 641 ms 49584 KB Output is correct
87 Correct 655 ms 49684 KB Output is correct