oj.uz

Submission #876005

# Submission time Handle Problem Language Result Execution time Memory
876005 2023-11-21T04:40:51 Z vjudge1 Network (BOI15_net) C++17
63 / 100
 4 ms 5216 KB 
#include <iostream>
#include <vector>
#include <tuple>
#include <queue>
#include <stack>
#include <deque>
#include <set>
#include <map>
#include <cmath>
#include <random>
#include <string>
#include <cassert>
#include <climits>
#include <algorithm>
#include <unordered_set>
#include <unordered_map>
using namespace std;

#define ll long long
#define f first
#define s second

void __print(int x) { cerr << x; }
void __print(long x) { cerr << x; }
void __print(long long x) { cerr << x; }
void __print(unsigned x) { cerr << x; }
void __print(unsigned long x) { cerr << x; }
void __print(unsigned long long x) { cerr << x; }
void __print(float x) { cerr << x; }
void __print(double x) { cerr << x; }
void __print(long double x) { cerr << x; }
void __print(char x) { cerr << '\'' << x << '\''; }
void __print(const char *x) { cerr << '\"' << x << '\"'; }
void __print(const string &x) { cerr << '\"' << x << '\"'; }
void __print(bool x) { cerr << (x ? "true" : "false"); }

template<typename A> void __print(const A &x);
template<typename A, typename B> void __print(const pair<A, B> &p);
template<typename... A> void __print(const tuple<A...> &t);
template<typename T> void __print(stack<T> s);
template<typename T> void __print(queue<T> q);
template<typename T, typename... U> void __print(priority_queue<T, U...> q);

template<typename A> void __print(const A &x) {
    bool first = true;
    cerr << '{';
    for (const auto &i : x) {
        cerr << (first ? "" : ","), __print(i);
        first = false;
    }
    cerr << '}';
}

template<typename A, typename B> void __print(const pair<A, B> &p) {
    cerr << '(';
    __print(p.f);
    cerr << ',';
    __print(p.s);
    cerr << ')';
}

template<typename... A> void __print(const tuple<A...> &t) {
    bool first = true;
    cerr << '(';
    apply([&first] (const auto &...args) { ((cerr << (first ? "" : ","), __print(args), first = false), ...); }, t);
    cerr << ')';
}

template<typename T> void __print(stack<T> s) {
    vector<T> debugVector;
    while (!s.empty()) {
        T t = s.top();
        debugVector.push_back(t);
        s.pop();
    }
    reverse(debugVector.begin(), debugVector.end());
    __print(debugVector);
}

template<typename T> void __print(queue<T> q) {
    vector<T> debugVector;
    while (!q.empty()) {
        T t = q.front();
        debugVector.push_back(t);
        q.pop();
    }
    __print(debugVector);
}

template<typename T, typename... U> void __print(priority_queue<T, U...> q) {
    vector<T> debugVector;
    while (!q.empty()) {
        T t = q.top();
        debugVector.push_back(t);
        q.pop();
    }
    __print(debugVector);
}

void _print() { cerr << "]\n"; }

template <typename Head, typename... Tail> void _print(const Head &H, const Tail &...T) {
    __print(H);
    if (sizeof...(T)) cerr << ", ";
    _print(T...);
}

#ifdef DEBUG
	#define D(...) cerr << "Line: " << __LINE__ << " [" << #__VA_ARGS__ << "] = ["; _print(__VA_ARGS__)
#else
	#define D(...)
#endif

int n, deg[100005], rt, idx, in[100005];
vector<int> adj[100005];
vector<pair<int, int>> leaf, ret;

void dfs(int curr, int par) {
	in[curr] = idx++;
	for (int i : adj[curr]) {
		if (i == par) continue;
		dfs(i, curr);
	}
}

int main() {

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

	cin >> n;
	for (int i = 0, a, b; i < n - 1; i++) {
		cin >> a >> b;
		adj[a].push_back(b);
		adj[b].push_back(a);
		deg[a]++;
		deg[b]++;
	}

	for (int i = 1; i <= n; i++) {
		if (deg[i] > 1) {
			rt = i;
			break;
		}
	}

	dfs(rt, -1);

	for (int i = 1; i <= n; i++) {
		if (deg[i] == 1) {
			leaf.push_back({in[i], i});
		}
	}
	sort(leaf.begin(), leaf.end());

	for (int i = 0; i < leaf.size() / 2; i++) {
		ret.push_back({leaf[i].s, leaf[i + leaf.size() / 2].s});
	}
	if (leaf.size() % 2) ret.push_back({leaf.back().s, leaf[0].s});

	cout << ret.size() << "\n";
	for (auto [a, b] : ret) {
		cout << a << " " << b << "\n";
	}

}

Compilation message

net.cpp: In function 'int main()':
net.cpp:156:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  156 |  for (int i = 0; i < leaf.size() / 2; i++) {
      |                  ~~^~~~~~~~~~~~~~~~~

Subtask #1
18.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2652 KB Output is correct
2 Correct 1 ms 2652 KB Output is correct
3 Correct 1 ms 2652 KB Output is correct
4 Correct 1 ms 2652 KB Output is correct
5 Correct 1 ms 2808 KB Output is correct
6 Correct 1 ms 2652 KB Output is correct
7 Correct 1 ms 2652 KB Output is correct
8 Correct 1 ms 2652 KB Output is correct
9 Correct 1 ms 2652 KB Output is correct
10 Correct 1 ms 2652 KB Output is correct
11 Correct 1 ms 2652 KB Output is correct
12 Correct 1 ms 2652 KB Output is correct
13 Correct 1 ms 2652 KB Output is correct
14 Correct 1 ms 2652 KB Output is correct
15 Correct 1 ms 2652 KB Output is correct
16 Correct 1 ms 2648 KB Output is correct
17 Correct 1 ms 2652 KB Output is correct
18 Correct 1 ms 2652 KB Output is correct
19 Correct 1 ms 2652 KB Output is correct
20 Correct 1 ms 2652 KB Output is correct

Subtask #2
45.0 / 45.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2652 KB Output is correct
2 Correct 1 ms 2652 KB Output is correct
3 Correct 1 ms 2652 KB Output is correct
4 Correct 1 ms 2652 KB Output is correct
5 Correct 1 ms 2808 KB Output is correct
6 Correct 1 ms 2652 KB Output is correct
7 Correct 1 ms 2652 KB Output is correct
8 Correct 1 ms 2652 KB Output is correct
9 Correct 1 ms 2652 KB Output is correct
10 Correct 1 ms 2652 KB Output is correct
11 Correct 1 ms 2652 KB Output is correct
12 Correct 1 ms 2652 KB Output is correct
13 Correct 1 ms 2652 KB Output is correct
14 Correct 1 ms 2652 KB Output is correct
15 Correct 1 ms 2652 KB Output is correct
16 Correct 1 ms 2648 KB Output is correct
17 Correct 1 ms 2652 KB Output is correct
18 Correct 1 ms 2652 KB Output is correct
19 Correct 1 ms 2652 KB Output is correct
20 Correct 1 ms 2652 KB Output is correct
21 Correct 1 ms 2652 KB Output is correct
22 Correct 1 ms 2908 KB Output is correct
23 Correct 2 ms 2904 KB Output is correct
24 Correct 2 ms 2824 KB Output is correct
25 Correct 2 ms 2904 KB Output is correct
26 Correct 1 ms 2908 KB Output is correct
27 Correct 1 ms 2908 KB Output is correct
28 Correct 1 ms 2908 KB Output is correct
29 Correct 1 ms 2904 KB Output is correct
30 Correct 1 ms 2652 KB Output is correct
31 Correct 1 ms 2904 KB Output is correct
32 Correct 1 ms 2652 KB Output is correct
33 Correct 1 ms 2652 KB Output is correct
34 Correct 1 ms 2904 KB Output is correct
35 Correct 1 ms 2652 KB Output is correct
36 Correct 1 ms 2652 KB Output is correct
37 Correct 1 ms 2816 KB Output is correct
38 Correct 1 ms 2652 KB Output is correct
39 Correct 1 ms 2652 KB Output is correct
40 Correct 1 ms 2816 KB Output is correct
41 Correct 1 ms 2648 KB Output is correct
42 Correct 1 ms 2652 KB Output is correct
43 Correct 1 ms 2656 KB Output is correct
44 Correct 1 ms 2660 KB Output is correct
45 Correct 1 ms 2660 KB Output is correct
46 Correct 1 ms 2652 KB Output is correct
47 Correct 1 ms 2652 KB Output is correct
48 Correct 1 ms 2652 KB Output is correct
49 Correct 1 ms 2652 KB Output is correct
50 Correct 1 ms 2652 KB Output is correct
51 Correct 1 ms 2652 KB Output is correct
52 Correct 1 ms 2652 KB Output is correct
53 Correct 1 ms 2652 KB Output is correct
54 Correct 1 ms 2652 KB Output is correct
55 Correct 1 ms 2652 KB Output is correct
56 Correct 1 ms 2652 KB Output is correct
57 Correct 1 ms 2648 KB Output is correct
58 Correct 1 ms 2904 KB Output is correct

Subtask #3
0 / 37.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2652 KB Output is correct
2 Correct 1 ms 2652 KB Output is correct
3 Correct 1 ms 2652 KB Output is correct
4 Correct 1 ms 2652 KB Output is correct
5 Correct 1 ms 2808 KB Output is correct
6 Correct 1 ms 2652 KB Output is correct
7 Correct 1 ms 2652 KB Output is correct
8 Correct 1 ms 2652 KB Output is correct
9 Correct 1 ms 2652 KB Output is correct
10 Correct 1 ms 2652 KB Output is correct
11 Correct 1 ms 2652 KB Output is correct
12 Correct 1 ms 2652 KB Output is correct
13 Correct 1 ms 2652 KB Output is correct
14 Correct 1 ms 2652 KB Output is correct
15 Correct 1 ms 2652 KB Output is correct
16 Correct 1 ms 2648 KB Output is correct
17 Correct 1 ms 2652 KB Output is correct
18 Correct 1 ms 2652 KB Output is correct
19 Correct 1 ms 2652 KB Output is correct
20 Correct 1 ms 2652 KB Output is correct
21 Correct 1 ms 2652 KB Output is correct
22 Correct 1 ms 2908 KB Output is correct
23 Correct 2 ms 2904 KB Output is correct
24 Correct 2 ms 2824 KB Output is correct
25 Correct 2 ms 2904 KB Output is correct
26 Correct 1 ms 2908 KB Output is correct
27 Correct 1 ms 2908 KB Output is correct
28 Correct 1 ms 2908 KB Output is correct
29 Correct 1 ms 2904 KB Output is correct
30 Correct 1 ms 2652 KB Output is correct
31 Correct 1 ms 2904 KB Output is correct
32 Correct 1 ms 2652 KB Output is correct
33 Correct 1 ms 2652 KB Output is correct
34 Correct 1 ms 2904 KB Output is correct
35 Correct 1 ms 2652 KB Output is correct
36 Correct 1 ms 2652 KB Output is correct
37 Correct 1 ms 2816 KB Output is correct
38 Correct 1 ms 2652 KB Output is correct
39 Correct 1 ms 2652 KB Output is correct
40 Correct 1 ms 2816 KB Output is correct
41 Correct 1 ms 2648 KB Output is correct
42 Correct 1 ms 2652 KB Output is correct
43 Correct 1 ms 2656 KB Output is correct
44 Correct 1 ms 2660 KB Output is correct
45 Correct 1 ms 2660 KB Output is correct
46 Correct 1 ms 2652 KB Output is correct
47 Correct 1 ms 2652 KB Output is correct
48 Correct 1 ms 2652 KB Output is correct
49 Correct 1 ms 2652 KB Output is correct
50 Correct 1 ms 2652 KB Output is correct
51 Correct 1 ms 2652 KB Output is correct
52 Correct 1 ms 2652 KB Output is correct
53 Correct 1 ms 2652 KB Output is correct
54 Correct 1 ms 2652 KB Output is correct
55 Correct 1 ms 2652 KB Output is correct
56 Correct 1 ms 2652 KB Output is correct
57 Correct 1 ms 2648 KB Output is correct
58 Correct 1 ms 2904 KB Output is correct
59 Runtime error 4 ms 5216 KB Execution killed with signal 11
60 Halted 0 ms 0 KB -