oj.uz

Submission #750502

# Submission time Handle Problem Language Result Execution time Memory
750502 2023-05-29T15:05:20 Z mat_v Network (BOI15_net) C++14
100 / 100
 465 ms 163316 KB 
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/rope>

#define ff(i,a,b) for(int (i) = (a); (i) <= (b); ++(i))
#define fb(i,a,b) for(int (i) = (a); (i) >= (b); --(i))
#define mod 998244353
#define xx first
#define yy second
#define all(a) (a).begin(), (a).end()
#define pb push_back
#define ll long long
#define pii pair<int,int>


using namespace std;
using namespace __gnu_pbds;
typedef tree<int, null_type, less<int>,rb_tree_tag, tree_order_statistics_node_update> ordered_set;/// find_by_order(x)(x+1th) , order_of_key() (strictly less)
mt19937 rnd(chrono::steady_clock::now().time_since_epoch().count());


int n;
vector<int> graf[5000005];
vector<int> lf;

void dfs(int x, int y){
    bool ima = 0;
    for(auto c:graf[x]){
        if(c == y)continue;
        ima = 1;
        dfs(c, x);
    }
    if(!ima)lf.pb(x);
}


int main()
{

    ios_base::sync_with_stdio(false); cin.tie(0);

    cin >> n;
    ff(i,1,n - 1){
        int a,b;
        cin >> a >> b;
        graf[a].pb(b);
        graf[b].pb(a);
    }
    int poc = 1;
    ff(i,1,n){
        if(graf[i].size()>1)poc = i;
    }
    dfs(poc,0);


    int vel = lf.size();
    cout << (vel+1) / 2 << "\n";
    ff(i,0,(vel/2)-1)cout << lf[i] << " " << lf[i + vel/2] << "\n";
    if(vel&1)cout << lf[0] << " " << lf[vel - 1] << "\n";

    return 0;
}

Compilation message

net.cpp: In function 'int main()':
net.cpp:6:27: warning: unnecessary parentheses in declaration of 'i' [-Wparentheses]
    6 | #define ff(i,a,b) for(int (i) = (a); (i) <= (b); ++(i))
      |                           ^
net.cpp:44:5: note: in expansion of macro 'ff'
   44 |     ff(i,1,n - 1){
      |     ^~
net.cpp:6:27: warning: unnecessary parentheses in declaration of 'i' [-Wparentheses]
    6 | #define ff(i,a,b) for(int (i) = (a); (i) <= (b); ++(i))
      |                           ^
net.cpp:51:5: note: in expansion of macro 'ff'
   51 |     ff(i,1,n){
      |     ^~
net.cpp:6:27: warning: unnecessary parentheses in declaration of 'i' [-Wparentheses]
    6 | #define ff(i,a,b) for(int (i) = (a); (i) <= (b); ++(i))
      |                           ^
net.cpp:59:5: note: in expansion of macro 'ff'
   59 |     ff(i,0,(vel/2)-1)cout << lf[i] << " " << lf[i + vel/2] << "\n";
      |     ^~

Subtask #1
18.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 55 ms 117620 KB Output is correct
2 Correct 58 ms 117684 KB Output is correct
3 Correct 61 ms 117604 KB Output is correct
4 Correct 56 ms 117708 KB Output is correct
5 Correct 61 ms 117720 KB Output is correct
6 Correct 58 ms 117636 KB Output is correct
7 Correct 54 ms 117644 KB Output is correct
8 Correct 56 ms 117708 KB Output is correct
9 Correct 56 ms 117704 KB Output is correct
10 Correct 62 ms 117616 KB Output is correct
11 Correct 54 ms 117620 KB Output is correct
12 Correct 55 ms 117620 KB Output is correct
13 Correct 55 ms 117700 KB Output is correct
14 Correct 59 ms 117672 KB Output is correct
15 Correct 55 ms 117724 KB Output is correct
16 Correct 66 ms 117700 KB Output is correct
17 Correct 57 ms 117624 KB Output is correct
18 Correct 53 ms 117724 KB Output is correct
19 Correct 55 ms 117724 KB Output is correct
20 Correct 56 ms 117708 KB Output is correct

Subtask #2
45.0 / 45.0

# Verdict Execution time Memory Grader output
1 Correct 55 ms 117620 KB Output is correct
2 Correct 58 ms 117684 KB Output is correct
3 Correct 61 ms 117604 KB Output is correct
4 Correct 56 ms 117708 KB Output is correct
5 Correct 61 ms 117720 KB Output is correct
6 Correct 58 ms 117636 KB Output is correct
7 Correct 54 ms 117644 KB Output is correct
8 Correct 56 ms 117708 KB Output is correct
9 Correct 56 ms 117704 KB Output is correct
10 Correct 62 ms 117616 KB Output is correct
11 Correct 54 ms 117620 KB Output is correct
12 Correct 55 ms 117620 KB Output is correct
13 Correct 55 ms 117700 KB Output is correct
14 Correct 59 ms 117672 KB Output is correct
15 Correct 55 ms 117724 KB Output is correct
16 Correct 66 ms 117700 KB Output is correct
17 Correct 57 ms 117624 KB Output is correct
18 Correct 53 ms 117724 KB Output is correct
19 Correct 55 ms 117724 KB Output is correct
20 Correct 56 ms 117708 KB Output is correct
21 Correct 55 ms 117648 KB Output is correct
22 Correct 55 ms 117796 KB Output is correct
23 Correct 57 ms 117840 KB Output is correct
24 Correct 58 ms 117836 KB Output is correct
25 Correct 57 ms 117828 KB Output is correct
26 Correct 59 ms 117692 KB Output is correct
27 Correct 58 ms 117808 KB Output is correct
28 Correct 67 ms 117720 KB Output is correct
29 Correct 55 ms 117804 KB Output is correct
30 Correct 54 ms 117684 KB Output is correct
31 Correct 55 ms 117832 KB Output is correct
32 Correct 58 ms 117708 KB Output is correct
33 Correct 57 ms 117724 KB Output is correct
34 Correct 55 ms 117684 KB Output is correct
35 Correct 57 ms 117660 KB Output is correct
36 Correct 56 ms 117672 KB Output is correct
37 Correct 55 ms 117760 KB Output is correct
38 Correct 57 ms 117676 KB Output is correct
39 Correct 65 ms 117632 KB Output is correct
40 Correct 59 ms 117708 KB Output is correct
41 Correct 59 ms 117728 KB Output is correct
42 Correct 54 ms 117664 KB Output is correct
43 Correct 60 ms 117776 KB Output is correct
44 Correct 56 ms 117652 KB Output is correct
45 Correct 55 ms 117648 KB Output is correct
46 Correct 55 ms 117708 KB Output is correct
47 Correct 55 ms 117644 KB Output is correct
48 Correct 60 ms 117620 KB Output is correct
49 Correct 61 ms 117756 KB Output is correct
50 Correct 57 ms 117604 KB Output is correct
51 Correct 63 ms 117648 KB Output is correct
52 Correct 57 ms 117720 KB Output is correct
53 Correct 56 ms 117784 KB Output is correct
54 Correct 57 ms 117712 KB Output is correct
55 Correct 56 ms 117792 KB Output is correct
56 Correct 54 ms 117644 KB Output is correct
57 Correct 58 ms 117800 KB Output is correct
58 Correct 55 ms 117836 KB Output is correct

Subtask #3
37.0 / 37.0

# Verdict Execution time Memory Grader output
1 Correct 55 ms 117620 KB Output is correct
2 Correct 58 ms 117684 KB Output is correct
3 Correct 61 ms 117604 KB Output is correct
4 Correct 56 ms 117708 KB Output is correct
5 Correct 61 ms 117720 KB Output is correct
6 Correct 58 ms 117636 KB Output is correct
7 Correct 54 ms 117644 KB Output is correct
8 Correct 56 ms 117708 KB Output is correct
9 Correct 56 ms 117704 KB Output is correct
10 Correct 62 ms 117616 KB Output is correct
11 Correct 54 ms 117620 KB Output is correct
12 Correct 55 ms 117620 KB Output is correct
13 Correct 55 ms 117700 KB Output is correct
14 Correct 59 ms 117672 KB Output is correct
15 Correct 55 ms 117724 KB Output is correct
16 Correct 66 ms 117700 KB Output is correct
17 Correct 57 ms 117624 KB Output is correct
18 Correct 53 ms 117724 KB Output is correct
19 Correct 55 ms 117724 KB Output is correct
20 Correct 56 ms 117708 KB Output is correct
21 Correct 55 ms 117648 KB Output is correct
22 Correct 55 ms 117796 KB Output is correct
23 Correct 57 ms 117840 KB Output is correct
24 Correct 58 ms 117836 KB Output is correct
25 Correct 57 ms 117828 KB Output is correct
26 Correct 59 ms 117692 KB Output is correct
27 Correct 58 ms 117808 KB Output is correct
28 Correct 67 ms 117720 KB Output is correct
29 Correct 55 ms 117804 KB Output is correct
30 Correct 54 ms 117684 KB Output is correct
31 Correct 55 ms 117832 KB Output is correct
32 Correct 58 ms 117708 KB Output is correct
33 Correct 57 ms 117724 KB Output is correct
34 Correct 55 ms 117684 KB Output is correct
35 Correct 57 ms 117660 KB Output is correct
36 Correct 56 ms 117672 KB Output is correct
37 Correct 55 ms 117760 KB Output is correct
38 Correct 57 ms 117676 KB Output is correct
39 Correct 65 ms 117632 KB Output is correct
40 Correct 59 ms 117708 KB Output is correct
41 Correct 59 ms 117728 KB Output is correct
42 Correct 54 ms 117664 KB Output is correct
43 Correct 60 ms 117776 KB Output is correct
44 Correct 56 ms 117652 KB Output is correct
45 Correct 55 ms 117648 KB Output is correct
46 Correct 55 ms 117708 KB Output is correct
47 Correct 55 ms 117644 KB Output is correct
48 Correct 60 ms 117620 KB Output is correct
49 Correct 61 ms 117756 KB Output is correct
50 Correct 57 ms 117604 KB Output is correct
51 Correct 63 ms 117648 KB Output is correct
52 Correct 57 ms 117720 KB Output is correct
53 Correct 56 ms 117784 KB Output is correct
54 Correct 57 ms 117712 KB Output is correct
55 Correct 56 ms 117792 KB Output is correct
56 Correct 54 ms 117644 KB Output is correct
57 Correct 58 ms 117800 KB Output is correct
58 Correct 55 ms 117836 KB Output is correct
59 Correct 353 ms 141916 KB Output is correct
60 Correct 402 ms 144376 KB Output is correct
61 Correct 61 ms 117708 KB Output is correct
62 Correct 56 ms 117628 KB Output is correct
63 Correct 308 ms 139264 KB Output is correct
64 Correct 58 ms 118036 KB Output is correct
65 Correct 64 ms 119428 KB Output is correct
66 Correct 150 ms 130796 KB Output is correct
67 Correct 465 ms 163316 KB Output is correct
68 Correct 440 ms 156444 KB Output is correct
69 Correct 69 ms 118604 KB Output is correct
70 Correct 117 ms 126952 KB Output is correct
71 Correct 303 ms 147540 KB Output is correct
72 Correct 329 ms 146324 KB Output is correct
73 Correct 134 ms 124712 KB Output is correct
74 Correct 402 ms 143288 KB Output is correct
75 Correct 97 ms 120904 KB Output is correct
76 Correct 304 ms 147268 KB Output is correct
77 Correct 290 ms 147220 KB Output is correct
78 Correct 74 ms 121040 KB Output is correct
79 Correct 450 ms 150880 KB Output is correct
80 Correct 60 ms 117872 KB Output is correct
81 Correct 141 ms 126944 KB Output is correct
82 Correct 348 ms 145280 KB Output is correct
83 Correct 392 ms 143292 KB Output is correct
84 Correct 410 ms 143300 KB Output is correct
85 Correct 465 ms 143320 KB Output is correct
86 Correct 406 ms 144348 KB Output is correct
87 Correct 411 ms 144396 KB Output is correct