Submission #93779

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
93779	2019-01-11T09:19:18 Z	kjain_1810	Network (BOI15_net)	C++11	63 / 100	7 ms	5240 KB

#include <bits/stdc++.h>
#define pb push_back
#define f first
#define s second
#define ind(a) scanf("%d", &a)
#define inlld(a) scanf("%lld", &a)
#define ind2(a, b) scanf("%d%d", &a, &b)
#define inlld2(a, b) scanf("%lld%lld", &a, &b)
#define ind3(a, b, c) scanf("%d%d%d", &a, &b, &c)
#define inlld3(a, b, c) scanf("%lld%lld%lld", &a, &b, &c)

using namespace std;

const int N=1e5+5;
const int MOD=1e9+7;

typedef long long ll;
typedef long double ld;

ll n;
vector<ll>adj[N], leaf, nonleaf;

void dfs(ll u, ll p)
{
    if(adj[u].size()==1)
        leaf.pb(u);
    else
        nonleaf.pb(u);
    for(auto v:adj[u])
        if(v!=p)
            dfs(v, u);
}

int main() 
{
    inlld(n);
    for(ll a=1; a<n; a++)
    {
        ll u, v;
        inlld2(u, v);
        adj[u].pb(v);
        adj[v].pb(u);
    }
    for(ll a=1; a<=n; a++)
        if(adj[a].size()>1)
        {
            dfs(a, 0);
            break;
        }
    ll ans=((int)leaf.size()+1)/2;
    printf("%lld\n", ans);
    for(ll a=0; a*2+1<leaf.size(); a++)
        printf("%lld %lld\n", leaf[a], leaf[a+(leaf.size()+1)/2]);
    if(leaf.size()%2==1)
        printf("%lld %lld\n", leaf[leaf.size()/2], leaf[0]);
    return 0;
}

Compilation message

net.cpp: In function 'int main()':
net.cpp:52:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(ll a=0; a*2+1<leaf.size(); a++)
                 ~~~~~^~~~~~~~~~~~
net.cpp:6:23: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
 #define inlld(a) scanf("%lld", &a)
                  ~~~~~^~~~~~~~~~~~
net.cpp:36:5: note: in expansion of macro 'inlld'
     inlld(n);
     ^~~~~
net.cpp:8:27: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
 #define inlld2(a, b) scanf("%lld%lld", &a, &b)
                      ~~~~~^~~~~~~~~~~~~~~~~~~~
net.cpp:40:9: note: in expansion of macro 'inlld2'
         inlld2(u, v);
         ^~~~~~

Subtask #1
18.0 / 18.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	4 ms	2680 KB	Output is correct
2	Correct	4 ms	2680 KB	Output is correct
3	Correct	4 ms	2680 KB	Output is correct
4	Correct	3 ms	2684 KB	Output is correct
5	Correct	4 ms	2680 KB	Output is correct
6	Correct	4 ms	2680 KB	Output is correct
7	Correct	4 ms	2680 KB	Output is correct
8	Correct	4 ms	2652 KB	Output is correct
9	Correct	4 ms	2680 KB	Output is correct
10	Correct	4 ms	2680 KB	Output is correct
11	Correct	4 ms	2680 KB	Output is correct
12	Correct	5 ms	2680 KB	Output is correct
13	Correct	4 ms	2680 KB	Output is correct
14	Correct	4 ms	2680 KB	Output is correct
15	Correct	3 ms	2680 KB	Output is correct
16	Correct	5 ms	2680 KB	Output is correct
17	Correct	4 ms	2680 KB	Output is correct
18	Correct	4 ms	2680 KB	Output is correct
19	Correct	4 ms	2680 KB	Output is correct
20	Correct	3 ms	2680 KB	Output is correct

Subtask #2
45.0 / 45.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	4 ms	2680 KB	Output is correct
2	Correct	4 ms	2680 KB	Output is correct
3	Correct	4 ms	2680 KB	Output is correct
4	Correct	3 ms	2684 KB	Output is correct
5	Correct	4 ms	2680 KB	Output is correct
6	Correct	4 ms	2680 KB	Output is correct
7	Correct	4 ms	2680 KB	Output is correct
8	Correct	4 ms	2652 KB	Output is correct
9	Correct	4 ms	2680 KB	Output is correct
10	Correct	4 ms	2680 KB	Output is correct
11	Correct	4 ms	2680 KB	Output is correct
12	Correct	5 ms	2680 KB	Output is correct
13	Correct	4 ms	2680 KB	Output is correct
14	Correct	4 ms	2680 KB	Output is correct
15	Correct	3 ms	2680 KB	Output is correct
16	Correct	5 ms	2680 KB	Output is correct
17	Correct	4 ms	2680 KB	Output is correct
18	Correct	4 ms	2680 KB	Output is correct
19	Correct	4 ms	2680 KB	Output is correct
20	Correct	3 ms	2680 KB	Output is correct
21	Correct	3 ms	2684 KB	Output is correct
22	Correct	4 ms	2860 KB	Output is correct
23	Correct	5 ms	2808 KB	Output is correct
24	Correct	4 ms	2808 KB	Output is correct
25	Correct	4 ms	2808 KB	Output is correct
26	Correct	4 ms	2808 KB	Output is correct
27	Correct	5 ms	2812 KB	Output is correct
28	Correct	5 ms	2808 KB	Output is correct
29	Correct	4 ms	2808 KB	Output is correct
30	Correct	4 ms	2680 KB	Output is correct
31	Correct	5 ms	2748 KB	Output is correct
32	Correct	4 ms	2680 KB	Output is correct
33	Correct	4 ms	2680 KB	Output is correct
34	Correct	4 ms	2680 KB	Output is correct
35	Correct	4 ms	2680 KB	Output is correct
36	Correct	4 ms	2680 KB	Output is correct
37	Correct	4 ms	2652 KB	Output is correct
38	Correct	4 ms	2680 KB	Output is correct
39	Correct	3 ms	2680 KB	Output is correct
40	Correct	4 ms	2680 KB	Output is correct
41	Correct	4 ms	2684 KB	Output is correct
42	Correct	4 ms	2680 KB	Output is correct
43	Correct	4 ms	2680 KB	Output is correct
44	Correct	4 ms	2680 KB	Output is correct
45	Correct	4 ms	2680 KB	Output is correct
46	Correct	4 ms	2680 KB	Output is correct
47	Correct	4 ms	2680 KB	Output is correct
48	Correct	4 ms	2680 KB	Output is correct
49	Correct	5 ms	2680 KB	Output is correct
50	Correct	4 ms	2680 KB	Output is correct
51	Correct	3 ms	2680 KB	Output is correct
52	Correct	4 ms	2680 KB	Output is correct
53	Correct	5 ms	2680 KB	Output is correct
54	Correct	4 ms	2684 KB	Output is correct
55	Correct	4 ms	2680 KB	Output is correct
56	Correct	4 ms	2680 KB	Output is correct
57	Correct	4 ms	2680 KB	Output is correct
58	Correct	4 ms	2808 KB	Output is correct

Subtask #3
0 / 37.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	4 ms	2680 KB	Output is correct
2	Correct	4 ms	2680 KB	Output is correct
3	Correct	4 ms	2680 KB	Output is correct
4	Correct	3 ms	2684 KB	Output is correct
5	Correct	4 ms	2680 KB	Output is correct
6	Correct	4 ms	2680 KB	Output is correct
7	Correct	4 ms	2680 KB	Output is correct
8	Correct	4 ms	2652 KB	Output is correct
9	Correct	4 ms	2680 KB	Output is correct
10	Correct	4 ms	2680 KB	Output is correct
11	Correct	4 ms	2680 KB	Output is correct
12	Correct	5 ms	2680 KB	Output is correct
13	Correct	4 ms	2680 KB	Output is correct
14	Correct	4 ms	2680 KB	Output is correct
15	Correct	3 ms	2680 KB	Output is correct
16	Correct	5 ms	2680 KB	Output is correct
17	Correct	4 ms	2680 KB	Output is correct
18	Correct	4 ms	2680 KB	Output is correct
19	Correct	4 ms	2680 KB	Output is correct
20	Correct	3 ms	2680 KB	Output is correct
21	Correct	3 ms	2684 KB	Output is correct
22	Correct	4 ms	2860 KB	Output is correct
23	Correct	5 ms	2808 KB	Output is correct
24	Correct	4 ms	2808 KB	Output is correct
25	Correct	4 ms	2808 KB	Output is correct
26	Correct	4 ms	2808 KB	Output is correct
27	Correct	5 ms	2812 KB	Output is correct
28	Correct	5 ms	2808 KB	Output is correct
29	Correct	4 ms	2808 KB	Output is correct
30	Correct	4 ms	2680 KB	Output is correct
31	Correct	5 ms	2748 KB	Output is correct
32	Correct	4 ms	2680 KB	Output is correct
33	Correct	4 ms	2680 KB	Output is correct
34	Correct	4 ms	2680 KB	Output is correct
35	Correct	4 ms	2680 KB	Output is correct
36	Correct	4 ms	2680 KB	Output is correct
37	Correct	4 ms	2652 KB	Output is correct
38	Correct	4 ms	2680 KB	Output is correct
39	Correct	3 ms	2680 KB	Output is correct
40	Correct	4 ms	2680 KB	Output is correct
41	Correct	4 ms	2684 KB	Output is correct
42	Correct	4 ms	2680 KB	Output is correct
43	Correct	4 ms	2680 KB	Output is correct
44	Correct	4 ms	2680 KB	Output is correct
45	Correct	4 ms	2680 KB	Output is correct
46	Correct	4 ms	2680 KB	Output is correct
47	Correct	4 ms	2680 KB	Output is correct
48	Correct	4 ms	2680 KB	Output is correct
49	Correct	5 ms	2680 KB	Output is correct
50	Correct	4 ms	2680 KB	Output is correct
51	Correct	3 ms	2680 KB	Output is correct
52	Correct	4 ms	2680 KB	Output is correct
53	Correct	5 ms	2680 KB	Output is correct
54	Correct	4 ms	2684 KB	Output is correct
55	Correct	4 ms	2680 KB	Output is correct
56	Correct	4 ms	2680 KB	Output is correct
57	Correct	4 ms	2680 KB	Output is correct
58	Correct	4 ms	2808 KB	Output is correct
59	Runtime error	7 ms	5240 KB	Execution killed with signal 11 (could be triggered by violating memory limits)
60	Halted	0 ms	0 KB	-

Submission #93779

Compilation message

Subtask #1 18.0 / 18.0

Subtask #2 45.0 / 45.0

Subtask #3 0 / 37.0

Subtask #1
18.0 / 18.0

Subtask #2
45.0 / 45.0

Subtask #3
0 / 37.0