Submission #130009

#	Time	Username	Problem	Language	Result	Execution time	Memory
130009		qkxwsm	Meetings (JOI19_meetings)	C++14	100 / 100	857 ms	1972 KiB

meetings

#pragma GCC optimize ("O3")
#pragma GCC target ("sse4")
#include <bits/stdc++.h>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/rope>
#include "meetings.h"

using namespace std;
using namespace __gnu_pbds;
using namespace __gnu_cxx;

random_device(rd);
mt19937 rng(rd());
const long long FIXED_RANDOM = chrono::steady_clock::now().time_since_epoch().count();

struct custom_hash
{
	template<class T>
	unsigned long long operator()(T v) const
	{
		unsigned long long x = v;
		x += FIXED_RANDOM;
		// x += 11400714819323198485ull;
		// x = (x ^ (x >> 30)) * 13787848793156543929ull;
		x = (x ^ (x >> 27)) * 10723151780598845931ull;
		return x ^ (x >> 31);
	}
};

template<class T> using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
template<class T, class U> using hash_table = gp_hash_table<T, U, custom_hash>;

template<class T>
T randomize(T mod)
{
	return (uniform_int_distribution<T>(0, mod - 1))(rng);
}
template<class T>
void readi(T &x)
{
	x = 0;
	bool negative = false;
	char c = ' ';
	while (c < '-')
	{
		c = getchar();
	}
	if (c == '-')
	{
		negative = true;
		c = getchar();
	}
	while (c >= '0')
	{
		x = x * 10 + (c - '0');
		c = getchar();
	}
	if (negative)
	{
		x = -x;
	}
}
template<class T>
void printi(T output)
{
	if (output == 0)
	{
		putchar('0');
		return;
	}
	if (output < 0)
	{
		putchar('-');
		output = -output;
	}
	int buf[20], n = 0;
	while(output)
	{
		buf[n] = ((output % 10));
		output /= 10;
		n++;
	}
	for (n--; n >= 0; n--)
	{
		putchar(buf[n] + '0');
	}
	return;
}
template<class T>
void ckmin(T &a, T b)
{
	a = min(a, b);
}
template<class T>
void ckmax(T &a, T b)
{
	a = max(a, b);
}
long long expo(long long a, long long e, long long mod)
{
	return ((e == 0) ? 1 : ((expo(a * a % mod, e >> 1, mod)) * ((e & 1) ? a : 1) % mod));
}
template<class T, class U>
void nmod(T &x, U mod)
{
	if (x >= mod) x -= mod;
}
template<class T>
T gcd(T a, T b)
{
	return (b ? gcd(b, a % b) : a);
}

#define y0 ___y0
#define y1 ___y1
#define MP make_pair
#define PB push_back
#define LB lower_bound
#define UB upper_bound
#define fi first
#define se second
#define DBG(x) cerr << #x << " = " << (x) << endl
#define SZ(x) ((int) ((x).size()))
#define FOR(i, a, b) for (auto i = (a); i < (b); i++)
#define FORD(i, a, b) for (auto i = (a) - 1; i >= (b); i--)
#define ALL(x) (x).begin(), (x).end()

const long double PI = 4.0 * atan(1.0);
const long double EPS = 1e-9;

#define MAGIC 347
#define SINF 10007
#define CO 1000007
#define INF 1000000007
#define BIG 1000000931
#define LARGE 1696969696967ll
#define GIANT 2564008813937411ll
#define LLINF 2696969696969696969ll
#define MAXN 2013

typedef long long ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
typedef pair<ld, ld> pdd;
typedef vector<int> vi;
typedef vector<ll> vl;
typedef vector<ld> vd;
typedef vector<pii> vpi;
typedef vector<pll> vpl;
typedef vector<pdd> vpd;

int N;
int S, T;
hash_table<int, int> res[MAXN];
vpi ans;
int queries = 0;

int ask(int a, int b, int c)
{
	queries++;
	assert(queries <= 100000);
	if (a > b) swap(a, b);
	if (b > c) swap(b, c);
	if (a > b) swap(a, b);
	if (res[a].find(b * N + c) != res[a].end())
	{
		return res[a][b * N + c];
	}
	int ret = Query(a, b, c);
	res[a][b * N + c] = ret;
	return ret;
}

bool cmp(int a, int b)
{
	return (ask(S, a, b) == a);
}

void solve(vi vec)
{
	if (SZ(vec) <= 1) return;
	FOR(i, 1, SZ(vec))
	{
		swap(vec[i], vec[randomize(i + 1)]);
	}
	// for (int v : vec)
	// {
	// 	DBG(v);
	// }
	// cerr << "yes\n";
	S = vec.back(); vec.pop_back();
	T = vec.back(); vec.pop_back();
	vi path;
	map<int, vi> mp;
	mp[S].PB(S); mp[T].PB(T);
	for (int u : vec)
	{
		int w = ask(S, u, T);
		if (w == u) path.PB(u);
		mp[w].PB(u);
	}
	if (!path.empty())
	{
		sort(ALL(path), cmp);
		ans.PB({S, path[0]});
		FOR(i, 0, SZ(path) - 1)
		{
			ans.PB({path[i], path[i + 1]});
		}
		ans.PB({path.back(), T});
	}
	else
	{
		ans.PB({S, T});
	}
	for (auto p : mp)
	{
		solve(p.se);
	}
}

void Solve(int n)
{
	N = n;
	if (N == 1)
	{
		return;
	}
	//everything has degree at most 18!
	//you want n * max
	//how can you find everybody that's connected to 0?
	vi lol;
	FOR(i, 0, N)
	{
		lol.PB(i);
	}
	solve(lol);
	for (pii p : ans)
	{
		if (p.fi > p.se) swap(p.fi, p.se);
		// cerr << "ye " << p.fi << ' ' << p.se << endl;
		Bridge(p.fi, p.se);
	}
}

• Subtask 1: 7 / 7
• Subtask 2: 10 / 10
• Subtask 3: 12 / 12
• Subtask 4: 71 / 71