oj.uz

Submission #538946

# Submission time Handle Problem Language Result Execution time Memory
538946 2022-03-18T05:19:37 Z Soul234 Network (BOI15_net) C++14
100 / 100
 477 ms 41096 KB 
#include<bits/stdc++.h>
using namespace std;

void DBG() { cerr << "]\n"; }
template<class H, class... T> void DBG(H h, T... t) {
    cerr << h; if(sizeof...(t)) cerr << ", ";
    DBG(t...);
}
#ifdef LOCAL
#define dbg(...) cerr << "[" << #__VA_ARGS__ << "]: [", DBG(__VA_ARGS__)
#else
#define dbg(...) 0
#endif // LOCAL

#define FOR(i,a,b) for(int i = (a) ; i<(b) ; i++)
#define F0R(i,a) FOR(i,0,a)
#define ROF(i,a,b) for(int i = (b)-1 ; i>=(a) ; i--)
#define R0F(i,a) ROF(i,0,a)
#define each(e,a) for(auto &e : (a))
#define sz(v) (int)(v).size()
#define all(v) (v).begin(),(v).end()
#define rall(v) (v).rbegin(),(v).rend()
#define pb push_back
#define tcT template<class T
#define nl "\n"

using ll = long long;
using vi = vector<int>;
using pi = pair<int,int>;
using str = string;
tcT> using V = vector<T>;
tcT> using pqg = priority_queue<T,vector<T>,greater<T>>;

void setIO(string NAME = "") {
    cin.tie(0)->sync_with_stdio(0);
    if(sz(NAME)) {
        freopen((NAME + ".inp").c_str(),"r",stdin);
        freopen((NAME + ".out").c_str(),"w",stdout);
    }
}

const int MX = 5e5+5;

int N;
vi adj[MX];
vi lfs;

void dfs(int u = 1, int p = -1) {
    if(sz(adj[u]) == 1) lfs.pb(u);
    each(v, adj[u]) if(v!=p) dfs(v, u);
}

void solve() {
    cin>>N;
    F0R(i,N-1) {
        int u,v;
        cin>>u>>v;
        adj[u].pb(v);
        adj[v].pb(u);
    }
    dfs();
    if(sz(lfs)&1) {
        cout << sz(lfs)/2+1 << nl;
        F0R(i,sz(lfs)/2) {
            cout << lfs[i] << " " << lfs[i+sz(lfs)/2+1] << nl;
        }
        cout << lfs[sz(lfs)/2] << " 1\n";
    }
    else {
        cout << sz(lfs)/2 << nl;
        F0R(i,sz(lfs)/2) {
            cout << lfs[i] << " " << lfs[i+sz(lfs)/2] << nl;
        }
    }
}

int main() {
    setIO();

    int t=1;
    //cin>>t;
    while(t-->0) {
        solve();
    }

    return 0;
}

Compilation message

net.cpp: In function 'void setIO(std::string)':
net.cpp:37:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   37 |         freopen((NAME + ".inp").c_str(),"r",stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
net.cpp:38:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   38 |         freopen((NAME + ".out").c_str(),"w",stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
18.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 8 ms 11988 KB Output is correct
2 Correct 7 ms 11988 KB Output is correct
3 Correct 7 ms 11988 KB Output is correct
4 Correct 7 ms 11988 KB Output is correct
5 Correct 7 ms 12064 KB Output is correct
6 Correct 7 ms 11988 KB Output is correct
7 Correct 6 ms 11996 KB Output is correct
8 Correct 7 ms 11972 KB Output is correct
9 Correct 6 ms 11988 KB Output is correct
10 Correct 6 ms 11988 KB Output is correct
11 Correct 7 ms 11988 KB Output is correct
12 Correct 8 ms 11936 KB Output is correct
13 Correct 7 ms 12024 KB Output is correct
14 Correct 8 ms 11976 KB Output is correct
15 Correct 7 ms 11988 KB Output is correct
16 Correct 6 ms 11980 KB Output is correct
17 Correct 6 ms 11988 KB Output is correct
18 Correct 7 ms 11988 KB Output is correct
19 Correct 6 ms 11988 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 8 ms 11988 KB Output is correct
2 Correct 7 ms 11988 KB Output is correct
3 Correct 7 ms 11988 KB Output is correct
4 Correct 7 ms 11988 KB Output is correct
5 Correct 7 ms 12064 KB Output is correct
6 Correct 7 ms 11988 KB Output is correct
7 Correct 6 ms 11996 KB Output is correct
8 Correct 7 ms 11972 KB Output is correct
9 Correct 6 ms 11988 KB Output is correct
10 Correct 6 ms 11988 KB Output is correct
11 Correct 7 ms 11988 KB Output is correct
12 Correct 8 ms 11936 KB Output is correct
13 Correct 7 ms 12024 KB Output is correct
14 Correct 8 ms 11976 KB Output is correct
15 Correct 7 ms 11988 KB Output is correct
16 Correct 6 ms 11980 KB Output is correct
17 Correct 6 ms 11988 KB Output is correct
18 Correct 7 ms 11988 KB Output is correct
19 Correct 6 ms 11988 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 10 ms 12036 KB Output is correct
25 Correct 9 ms 12072 KB Output is correct
26 Correct 9 ms 12116 KB Output is correct
27 Correct 8 ms 12116 KB Output is correct
28 Correct 7 ms 12136 KB Output is correct
29 Correct 9 ms 12116 KB Output is correct
30 Correct 8 ms 11988 KB Output is correct
31 Correct 7 ms 12116 KB Output is correct
32 Correct 6 ms 11988 KB Output is correct
33 Correct 8 ms 12064 KB Output is correct
34 Correct 7 ms 11988 KB Output is correct
35 Correct 7 ms 11988 KB Output is correct
36 Correct 6 ms 11988 KB Output is correct
37 Correct 6 ms 11988 KB Output is correct
38 Correct 8 ms 12116 KB Output is correct
39 Correct 8 ms 11988 KB Output is correct
40 Correct 7 ms 11988 KB Output is correct
41 Correct 7 ms 12024 KB Output is correct
42 Correct 6 ms 11988 KB Output is correct
43 Correct 6 ms 11988 KB Output is correct
44 Correct 6 ms 11988 KB Output is correct
45 Correct 6 ms 11988 KB Output is correct
46 Correct 7 ms 11988 KB Output is correct
47 Correct 6 ms 11988 KB Output is correct
48 Correct 6 ms 11988 KB Output is correct
49 Correct 7 ms 12116 KB Output is correct
50 Correct 6 ms 11988 KB Output is correct
51 Correct 7 ms 11988 KB Output is correct
52 Correct 9 ms 11988 KB Output is correct
53 Correct 9 ms 11988 KB Output is correct
54 Correct 6 ms 11988 KB Output is correct
55 Correct 7 ms 11988 KB Output is correct
56 Correct 6 ms 12064 KB Output is correct
57 Correct 7 ms 11988 KB Output is correct
58 Correct 7 ms 12116 KB Output is correct

Subtask #3
37.0 / 37.0

# Verdict Execution time Memory Grader output
1 Correct 8 ms 11988 KB Output is correct
2 Correct 7 ms 11988 KB Output is correct
3 Correct 7 ms 11988 KB Output is correct
4 Correct 7 ms 11988 KB Output is correct
5 Correct 7 ms 12064 KB Output is correct
6 Correct 7 ms 11988 KB Output is correct
7 Correct 6 ms 11996 KB Output is correct
8 Correct 7 ms 11972 KB Output is correct
9 Correct 6 ms 11988 KB Output is correct
10 Correct 6 ms 11988 KB Output is correct
11 Correct 7 ms 11988 KB Output is correct
12 Correct 8 ms 11936 KB Output is correct
13 Correct 7 ms 12024 KB Output is correct
14 Correct 8 ms 11976 KB Output is correct
15 Correct 7 ms 11988 KB Output is correct
16 Correct 6 ms 11980 KB Output is correct
17 Correct 6 ms 11988 KB Output is correct
18 Correct 7 ms 11988 KB Output is correct
19 Correct 6 ms 11988 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 10 ms 12036 KB Output is correct
25 Correct 9 ms 12072 KB Output is correct
26 Correct 9 ms 12116 KB Output is correct
27 Correct 8 ms 12116 KB Output is correct
28 Correct 7 ms 12136 KB Output is correct
29 Correct 9 ms 12116 KB Output is correct
30 Correct 8 ms 11988 KB Output is correct
31 Correct 7 ms 12116 KB Output is correct
32 Correct 6 ms 11988 KB Output is correct
33 Correct 8 ms 12064 KB Output is correct
34 Correct 7 ms 11988 KB Output is correct
35 Correct 7 ms 11988 KB Output is correct
36 Correct 6 ms 11988 KB Output is correct
37 Correct 6 ms 11988 KB Output is correct
38 Correct 8 ms 12116 KB Output is correct
39 Correct 8 ms 11988 KB Output is correct
40 Correct 7 ms 11988 KB Output is correct
41 Correct 7 ms 12024 KB Output is correct
42 Correct 6 ms 11988 KB Output is correct
43 Correct 6 ms 11988 KB Output is correct
44 Correct 6 ms 11988 KB Output is correct
45 Correct 6 ms 11988 KB Output is correct
46 Correct 7 ms 11988 KB Output is correct
47 Correct 6 ms 11988 KB Output is correct
48 Correct 6 ms 11988 KB Output is correct
49 Correct 7 ms 12116 KB Output is correct
50 Correct 6 ms 11988 KB Output is correct
51 Correct 7 ms 11988 KB Output is correct
52 Correct 9 ms 11988 KB Output is correct
53 Correct 9 ms 11988 KB Output is correct
54 Correct 6 ms 11988 KB Output is correct
55 Correct 7 ms 11988 KB Output is correct
56 Correct 6 ms 12064 KB Output is correct
57 Correct 7 ms 11988 KB Output is correct
58 Correct 7 ms 12116 KB Output is correct
59 Correct 334 ms 30000 KB Output is correct
60 Correct 411 ms 32072 KB Output is correct
61 Correct 7 ms 11988 KB Output is correct
62 Correct 9 ms 11988 KB Output is correct
63 Correct 283 ms 28276 KB Output is correct
64 Correct 8 ms 12372 KB Output is correct
65 Correct 16 ms 13648 KB Output is correct
66 Correct 114 ms 25540 KB Output is correct
67 Correct 466 ms 40236 KB Output is correct
68 Correct 477 ms 41096 KB Output is correct
69 Correct 16 ms 12756 KB Output is correct
70 Correct 99 ms 19164 KB Output is correct
71 Correct 258 ms 35116 KB Output is correct
72 Correct 306 ms 34424 KB Output is correct
73 Correct 87 ms 17376 KB Output is correct
74 Correct 378 ms 30984 KB Output is correct
75 Correct 36 ms 14528 KB Output is correct
76 Correct 308 ms 34776 KB Output is correct
77 Correct 258 ms 35084 KB Output is correct
78 Correct 25 ms 14640 KB Output is correct
79 Correct 419 ms 38444 KB Output is correct
80 Correct 8 ms 12244 KB Output is correct
81 Correct 85 ms 19220 KB Output is correct
82 Correct 354 ms 33008 KB Output is correct
83 Correct 416 ms 30952 KB Output is correct
84 Correct 381 ms 31036 KB Output is correct
85 Correct 374 ms 30964 KB Output is correct
86 Correct 372 ms 32144 KB Output is correct
87 Correct 431 ms 32056 KB Output is correct