oj.uz

Submission #801819

# Submission time Handle Problem Language Result Execution time Memory
801819 2023-08-02T07:54:06 Z arush_agu Network (BOI15_net) C++17
100 / 100
 1210 ms 56524 KB 
#include <algorithm>
#include <cctype>
#include <cmath>
#include <cstdio>
#include <cstring>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#include <functional>
#include <iomanip>
#include <iostream>
#include <iterator>
#include <list>
#include <map>
#include <numeric>
#include <queue>
#include <random>
#include <set>
#include <sstream>
#include <stack>
#include <string>
#include <unordered_map>
#include <unordered_set>
#include <vector>

#ifdef DEBUG
#include <time.h>
#endif

#define all(a) (a).begin(), (a).end()
#define rev(a) (a).rbegin(), (a).rend()
#define F first
#define S second
int recur_depth = 0;
#ifdef DEBUG
#define dbg(x)                                                                 \
  {                                                                            \
    ++recur_depth;                                                             \
    auto x_ = x;                                                               \
    --recur_depth;                                                             \
    cerr << string(recur_depth, '\t') << "\e[91m" << __func__ << ":"           \
         << __LINE__ << "\t" << #x << " = " << x_ << "\e[39m" << endl;         \
  }
#else
#define dbg(x)
#endif

using namespace std;
using namespace __gnu_pbds;

typedef pair<int, int> ii;

typedef long long ll;
typedef long double ld;
typedef pair<ll, ll> llll;

typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<pair<int, int>> vii;
typedef vector<vii> vvii;

typedef vector<ll> vl;
typedef vector<vl> vvl;
typedef vector<pair<ll, ll>> vll;
typedef vector<vll> vvll;

typedef vector<bool> vb;

template <class type1>
using ordered_set = tree<type1, null_type, less<type1>, rb_tree_tag,
                         tree_order_statistics_node_update>;

template <typename A, typename B>
ostream &operator<<(ostream &os, const pair<A, B> &p) {
  return os << '(' << p.first << ", " << p.second << ')';
}
template <typename T_container, typename T = typename enable_if<
                                    !is_same<T_container, string>::value,
                                    typename T_container::value_type>::type>
ostream &operator<<(ostream &os, const T_container &v) {
  os << '{';
  string sep;
  for (const T &x : v)
    os << sep << x, sep = ", ";
  return os << '}';
}

const ll MOD = 1e9 + 7;
// const ll MOD = 998244353;
const ll INF = 1e9;
const ld EPS = 1e-9;

void solve() {
  int n;
  cin >> n;
  vvi adj(n);
  for (int i = 0; i < n - 1; i++) {
    int u, v;
    cin >> u >> v;
    u--, v--;
    adj[u].push_back(v), adj[v].push_back(u);
  }

  int t = 0;
  vi ls;
  function<void(int, int)> f = [&](int u, int p) {
    t++;
    if (adj[u].size() == 1 && p != -1)
      ls.push_back(u + 1);
    for (int &v : adj[u])
      if (v != p)
        f(v, u);
  };
  for (int i = 0; i < n; i++)
    if (adj[i].size() > 1) {
      f(i, -1);
      break;
    }

  cerr << ls << "\n";
  cout << (ls.size() + 1) / 2 << "\n";
  for (int i = 0; 2 * i < ls.size(); i++)
    cout << ls[i] << " " << ls[i + ls.size() / 2] << "\n";
}
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(NULL);

  clock_t start = clock();

  int test_cases = 1;
  // cin >> test_cases;

  while (test_cases--)
    solve();

#ifdef DEBUG
  cerr << fixed << setprecision(10)
       << "\nTime Taken: " << (double)(clock() - start) / CLOCKS_PER_SEC
       << "s\n";
#endif
  return 0;
}

Compilation message

net.cpp: In function 'void solve()':
net.cpp:121:25: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  121 |   for (int i = 0; 2 * i < ls.size(); i++)
      |                   ~~~~~~^~~~~~~~~~~
net.cpp: In function 'int main()':
net.cpp:128:11: warning: unused variable 'start' [-Wunused-variable]
  128 |   clock_t start = clock();
      |           ^~~~~

Subtask #1
18.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 256 KB Output is correct
2 Correct 1 ms 256 KB Output is correct
3 Correct 1 ms 212 KB Output is correct
4 Correct 1 ms 212 KB Output is correct
5 Correct 1 ms 316 KB Output is correct
6 Correct 1 ms 212 KB Output is correct
7 Correct 1 ms 320 KB Output is correct
8 Correct 1 ms 212 KB Output is correct
9 Correct 1 ms 212 KB Output is correct
10 Correct 1 ms 212 KB Output is correct
11 Correct 1 ms 212 KB Output is correct
12 Correct 1 ms 212 KB Output is correct
13 Correct 1 ms 212 KB Output is correct
14 Correct 1 ms 212 KB Output is correct
15 Correct 1 ms 324 KB Output is correct
16 Correct 1 ms 316 KB Output is correct
17 Correct 1 ms 320 KB Output is correct
18 Correct 1 ms 316 KB Output is correct
19 Correct 1 ms 212 KB Output is correct
20 Correct 1 ms 320 KB Output is correct

Subtask #2
45.0 / 45.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 256 KB Output is correct
2 Correct 1 ms 256 KB Output is correct
3 Correct 1 ms 212 KB Output is correct
4 Correct 1 ms 212 KB Output is correct
5 Correct 1 ms 316 KB Output is correct
6 Correct 1 ms 212 KB Output is correct
7 Correct 1 ms 320 KB Output is correct
8 Correct 1 ms 212 KB Output is correct
9 Correct 1 ms 212 KB Output is correct
10 Correct 1 ms 212 KB Output is correct
11 Correct 1 ms 212 KB Output is correct
12 Correct 1 ms 212 KB Output is correct
13 Correct 1 ms 212 KB Output is correct
14 Correct 1 ms 212 KB Output is correct
15 Correct 1 ms 324 KB Output is correct
16 Correct 1 ms 316 KB Output is correct
17 Correct 1 ms 320 KB Output is correct
18 Correct 1 ms 316 KB Output is correct
19 Correct 1 ms 212 KB Output is correct
20 Correct 1 ms 320 KB Output is correct
21 Correct 1 ms 212 KB Output is correct
22 Correct 5 ms 460 KB Output is correct
23 Correct 5 ms 468 KB Output is correct
24 Correct 5 ms 420 KB Output is correct
25 Correct 5 ms 468 KB Output is correct
26 Correct 3 ms 324 KB Output is correct
27 Correct 4 ms 468 KB Output is correct
28 Correct 4 ms 420 KB Output is correct
29 Correct 3 ms 328 KB Output is correct
30 Correct 1 ms 212 KB Output is correct
31 Correct 4 ms 468 KB Output is correct
32 Correct 1 ms 212 KB Output is correct
33 Correct 1 ms 212 KB Output is correct
34 Correct 1 ms 212 KB Output is correct
35 Correct 1 ms 212 KB Output is correct
36 Correct 1 ms 324 KB Output is correct
37 Correct 1 ms 340 KB Output is correct
38 Correct 1 ms 340 KB Output is correct
39 Correct 1 ms 212 KB Output is correct
40 Correct 1 ms 256 KB Output is correct
41 Correct 2 ms 320 KB Output is correct
42 Correct 2 ms 320 KB Output is correct
43 Correct 3 ms 340 KB Output is correct
44 Correct 1 ms 212 KB Output is correct
45 Correct 1 ms 340 KB Output is correct
46 Correct 2 ms 340 KB Output is correct
47 Correct 1 ms 212 KB Output is correct
48 Correct 1 ms 316 KB Output is correct
49 Correct 3 ms 340 KB Output is correct
50 Correct 1 ms 212 KB Output is correct
51 Correct 1 ms 212 KB Output is correct
52 Correct 1 ms 340 KB Output is correct
53 Correct 2 ms 340 KB Output is correct
54 Correct 1 ms 212 KB Output is correct
55 Correct 2 ms 340 KB Output is correct
56 Correct 1 ms 212 KB Output is correct
57 Correct 2 ms 340 KB Output is correct
58 Correct 5 ms 464 KB Output is correct

Subtask #3
37.0 / 37.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 256 KB Output is correct
2 Correct 1 ms 256 KB Output is correct
3 Correct 1 ms 212 KB Output is correct
4 Correct 1 ms 212 KB Output is correct
5 Correct 1 ms 316 KB Output is correct
6 Correct 1 ms 212 KB Output is correct
7 Correct 1 ms 320 KB Output is correct
8 Correct 1 ms 212 KB Output is correct
9 Correct 1 ms 212 KB Output is correct
10 Correct 1 ms 212 KB Output is correct
11 Correct 1 ms 212 KB Output is correct
12 Correct 1 ms 212 KB Output is correct
13 Correct 1 ms 212 KB Output is correct
14 Correct 1 ms 212 KB Output is correct
15 Correct 1 ms 324 KB Output is correct
16 Correct 1 ms 316 KB Output is correct
17 Correct 1 ms 320 KB Output is correct
18 Correct 1 ms 316 KB Output is correct
19 Correct 1 ms 212 KB Output is correct
20 Correct 1 ms 320 KB Output is correct
21 Correct 1 ms 212 KB Output is correct
22 Correct 5 ms 460 KB Output is correct
23 Correct 5 ms 468 KB Output is correct
24 Correct 5 ms 420 KB Output is correct
25 Correct 5 ms 468 KB Output is correct
26 Correct 3 ms 324 KB Output is correct
27 Correct 4 ms 468 KB Output is correct
28 Correct 4 ms 420 KB Output is correct
29 Correct 3 ms 328 KB Output is correct
30 Correct 1 ms 212 KB Output is correct
31 Correct 4 ms 468 KB Output is correct
32 Correct 1 ms 212 KB Output is correct
33 Correct 1 ms 212 KB Output is correct
34 Correct 1 ms 212 KB Output is correct
35 Correct 1 ms 212 KB Output is correct
36 Correct 1 ms 324 KB Output is correct
37 Correct 1 ms 340 KB Output is correct
38 Correct 1 ms 340 KB Output is correct
39 Correct 1 ms 212 KB Output is correct
40 Correct 1 ms 256 KB Output is correct
41 Correct 2 ms 320 KB Output is correct
42 Correct 2 ms 320 KB Output is correct
43 Correct 3 ms 340 KB Output is correct
44 Correct 1 ms 212 KB Output is correct
45 Correct 1 ms 340 KB Output is correct
46 Correct 2 ms 340 KB Output is correct
47 Correct 1 ms 212 KB Output is correct
48 Correct 1 ms 316 KB Output is correct
49 Correct 3 ms 340 KB Output is correct
50 Correct 1 ms 212 KB Output is correct
51 Correct 1 ms 212 KB Output is correct
52 Correct 1 ms 340 KB Output is correct
53 Correct 2 ms 340 KB Output is correct
54 Correct 1 ms 212 KB Output is correct
55 Correct 2 ms 340 KB Output is correct
56 Correct 1 ms 212 KB Output is correct
57 Correct 2 ms 340 KB Output is correct
58 Correct 5 ms 464 KB Output is correct
59 Correct 908 ms 37124 KB Output is correct
60 Correct 978 ms 41320 KB Output is correct
61 Correct 1 ms 212 KB Output is correct
62 Correct 1 ms 212 KB Output is correct
63 Correct 880 ms 33576 KB Output is correct
64 Correct 3 ms 980 KB Output is correct
65 Correct 9 ms 3280 KB Output is correct
66 Correct 140 ms 25608 KB Output is correct
67 Correct 494 ms 55316 KB Output is correct
68 Correct 454 ms 56524 KB Output is correct
69 Correct 40 ms 1612 KB Output is correct
70 Correct 325 ms 14316 KB Output is correct
71 Correct 1210 ms 45756 KB Output is correct
72 Correct 1161 ms 44204 KB Output is correct
73 Correct 193 ms 11080 KB Output is correct
74 Correct 902 ms 39628 KB Output is correct
75 Correct 119 ms 5164 KB Output is correct
76 Correct 1173 ms 45336 KB Output is correct
77 Correct 1173 ms 45484 KB Output is correct
78 Correct 40 ms 5832 KB Output is correct
79 Correct 354 ms 52360 KB Output is correct
80 Correct 8 ms 644 KB Output is correct
81 Correct 307 ms 14468 KB Output is correct
82 Correct 985 ms 42416 KB Output is correct
83 Correct 826 ms 39672 KB Output is correct
84 Correct 823 ms 39564 KB Output is correct
85 Correct 798 ms 39564 KB Output is correct
86 Correct 953 ms 41404 KB Output is correct
87 Correct 992 ms 41384 KB Output is correct