Submission #963993

#	Time	Username	Problem	Language	Result	Execution time	Memory
963993		vjudge1	Meetings 2 (JOI21_meetings2)	C++17	20 / 100	4035 ms	57548 KiB

meetings2

// #pragma GCC target("avx2")
// #pragma GCC optimize("O3")
// #include <x86intrin.h>

#include <bits/stdc++.h>
#include <chrono>
#include <random>

// @author: Vlapos

namespace operators
{
	template <typename T1, typename T2>
	std::istream &operator>>(std::istream &in, std::pair<T1, T2> &x)
	{
		in >> x.first >> x.second;
		return in;
	}

	template <typename T1, typename T2>
	std::ostream &operator<<(std::ostream &out, std::pair<T1, T2> x)
	{
		out << x.first << " " << x.second;
		return out;
	}

	template <typename T1>
	std::istream &operator>>(std::istream &in, std::vector<T1> &x)
	{
		for (auto &i : x)
			in >> i;
		return in;
	}

	template <typename T1>
	std::ostream &operator<<(std::ostream &out, std::vector<T1> &x)
	{
		for (auto &i : x)
			out << i << " ";
		return out;
	}

	template <typename T1>
	std::ostream &operator<<(std::ostream &out, std::set<T1> &x)
	{
		for (auto &i : x)
			out << i << " ";
		return out;
	}
}

// name spaces
using namespace std;
using namespace operators;
// end of name spaces

// defines
#define ll long long
#define ull unsigned long long
#define pb push_back
#define mp make_pair
#define pii pair<int, int>
#define pll pair<ll, ll>
#define f first
#define s second
#define uint unsigned int
#define all(vc) vc.begin(), vc.end()
// end of defines

// usefull stuff

void boost()
{
	ios_base ::sync_with_stdio(false);
	cin.tie(0);
	cout.tie(0);
}

inline int getbit(int &x, int &bt) { return (x >> bt) & 1; }

const int dx4[4] = {-1, 0, 0, 1};
const int dy4[4] = {0, -1, 1, 0};
const int dx8[8] = {-1, -1, -1, 0, 0, 1, 1, 1};
const int dy8[8] = {-1, -0, 1, -1, 1, -1, 0, 1};

const ll INF = (1e18) + 500;
const int BIG = (1e9) * 2 + 100;
const int MAXN = (1e5) + 5;
const int MOD7 = (1e9) + 7;
const int MOD9 = (1e9) + 9;
const uint MODFFT = 998244353;

// #define int ll

struct test
{
	vector<vector<int>> tree;
	vector<int> answers, used;
	int n;

	int dfsC(int v, int szA, int pr = -1)
	{
		for (auto tov : tree[v])
			if (!used[tov] and tov != pr and szA < sz[{tov, v}] * 2)
				return dfsC(tov, szA, v);
		return v;
	}

	map<pii, int> sz;
	vector<vector<pii>> els;
	vector<int> u, MX, SZ;

	void dfsAdd(int v, int d, int pr, int RT, int A)
	{
		int P = min(sz[{v, pr}], A);
		answers[P * 2] = max(answers[P * 2], d + 1);
		els[RT].pb({sz[{v, pr}], d});
		for (auto tov : tree[v])
			if (tov != pr and !used[tov])
				dfsAdd(tov, d + 1, v, RT, A);
	}

	void dfsSz(int v, int pr = -1)
	{
		SZ[v] = 1;
		for (auto tov : tree[v])
			if (tov != pr and !used[tov])
			{
				dfsSz(tov, v);
				SZ[v] += SZ[tov];
			}
	}

	void doSz(int v, int pr = -1)
	{
		int cSz = 1;
		for (auto tov : tree[v])
			if (tov != pr and !used[tov])
			{
				doSz(tov, v);
				int toSz = sz[{tov, v}];
				cSz += toSz;
				sz[{v, tov}] = n - toSz;
			}
		if (pr != -1)
			sz[{v, pr}] = cSz;
	}

	void getAns(int v)
	{
		dfsSz(v);
		v = dfsC(v, SZ[v]);
		used[v] = 1;

		priority_queue<pii> cur;
		set<pii> WTF;

		int CNT = 0;
		for (auto tov : tree[v])
			if (!used[tov])
			{
				CNT++;
				dfsAdd(tov, 1, v, tov, n - sz[{tov, v}]);
				sort(all(els[tov]));
				reverse(all(els[tov]));
				cur.push({els[tov][0].f, tov});
				WTF.insert({1, tov});
				MX[tov] = -1;
			}
		if (CNT > 1)
		{
			while (cur.size())
			{
				pii bf = cur.top();
				cur.pop();
				auto [sz, rt] = bf;

				int cMx = WTF.begin()->s == rt ? next(WTF.begin())->f : WTF.begin()->f;
				cMx = -cMx;
				if (cMx != -1 and sz * 2 <= n)
				{
					answers[sz * 2] = max(answers[sz * 2], cMx + 1 + els[rt][u[rt]].s);
				}

				WTF.erase({-MX[rt], rt});
				MX[rt] = max(MX[rt], els[rt][u[rt]].s);
				WTF.insert({-MX[rt], rt});

				u[bf.s]++;
				if (els[bf.s].size() > u[bf.s])
					cur.push({els[bf.s][u[bf.s]].f, bf.s});
			}
		}

		for (auto tov : tree[v])
			if (!used[tov])
			{
				u[tov] = 0;
				els[tov].clear();
				els[tov].shrink_to_fit();
			}
		for (auto tov : tree[v])
			if (!used[tov])
				getAns(tov);
	}

	void solve(int testcase)
	{
		boost();

		cin >> n;

		used.resize(n);
		tree.resize(n);
		SZ.resize(n);
		answers.resize(n + 1);
		if (2 <= n)
			answers[2] = 2;
		MX.resize(n);
		els.resize(n);
		u.resize(n);
		for (int i = 0; i < n - 1; ++i)
		{
			int v, tov;
			cin >> v >> tov;
			--v, --tov;
			tree[v].pb(tov);
			tree[tov].pb(v);
		}

		doSz(0, -1);
		getAns(0);
		for (int i = (n / 2) * 2 - 2; i > 0; i -= 2)
		{
			answers[i] = max(answers[i], answers[i + 2]);
		}

		for (int i = 1; i <= n; ++i)
		{
			int cur = max(1, answers[i]);
			cout << cur << "\n";
		}
	}
};

main()
{
	boost();
	int q = 1;
	// cin >> q;
	for (int i = 0; i < q; i++)
	{
		test t;
		t.solve(i);
	}
	return 0;
}
//[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]//
//                                                                                    //
//                               Coded by Der_Vlἀpos                                  //
//                                                                                    //
//[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]//

Compilation message (stderr)

meetings2.cpp: In member function 'void test::getAns(int)':
meetings2.cpp:190:26: warning: comparison of integer expressions of different signedness: 'std::vector<std::pair<int, int> >::size_type' {aka 'long unsigned int'} and '__gnu_cxx::__alloc_traits<std::allocator<int>, int>::value_type' {aka 'int'} [-Wsign-compare]
  190 |     if (els[bf.s].size() > u[bf.s])
meetings2.cpp: At global scope:
meetings2.cpp:246:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
  246 | main()
      | ^~~~

• Subtask 1: 4 / 4
• Subtask 2: 16 / 16
• Subtask 3: 0 / 80