Submission #969744

#	Time	Username	Problem	Language	Result	Execution time	Memory
969744		penguin133	Park (JOI17_park)	C++17	20 / 100	564 ms	1212 KiB

park

#include <bits/stdc++.h>
using namespace std;
#include "park.h"
//#define int long long
#define pi pair<int, int>
#define pii pair<int, pi>
#define fi first
#define se second
#ifdef _WIN32
#define getchar_unlocked _getchar_nolock
#endif
mt19937_64 rng(123);

static int Place[1400], p2[1400];
const int szz = 8;
void dnc(vector <int> shit){
	if(shit.size() <= 1)return;
	if(shit.size() <= szz){
		for(int i = 0; i < (int)shit.size(); i++){
			for(int j = i + 1; j < (int)shit.size(); j++){
				int x = shit[i], y = shit[j];
				Place[x] = Place[y] = 1;
				if(x > y)swap(x, y);
				if(Ask(x, y, Place))Answer(x, y);
				Place[x] = Place[y] = 0;
			}
		}
		return;
	}
	vector <int> nxtstuff, die[7];
	int bru = shit[rng()%shit.size()];
	for(int i = 0; i < (int)shit.size(); i++){
		if(shit[i] == bru)continue;
		Place[bru] = Place[shit[i]] = 1;
		int a = bru, b = shit[i];
		if(a > b)swap(a, b);
		if(Ask(a, b, Place)){
			nxtstuff.push_back(shit[i]);
			Answer(a, b);
		}
		Place[bru] = Place[shit[i]] = 0;
	}
	for(int i = 0; i < 1400; i++)p2[i] = 0;
	for(auto i : shit)p2[i] = 1;
	for(auto i : shit){
		if(i == bru)continue;
		bool f = 0;
		for(auto j : nxtstuff)if(i == j)f = 1;
		if(f)continue;
		int lo = 0, hi = (int)nxtstuff.size() - 2, tmp = (int)nxtstuff.size() - 1;
		while(lo <= hi){
			int mid = (lo + hi) >> 1;
			for(int k = mid + 1; k < (int)nxtstuff.size(); k++)p2[nxtstuff[k]] = 0;
			int a = bru, b = i;
			if(a > b)swap(a, b);
			int res = Ask(a, b, p2);
			for(auto k : nxtstuff)p2[k] = 1;
			if(res){
				tmp = mid;
				hi = mid - 1;
			}
			else lo = mid + 1;
		}
		die[tmp].push_back(i);
	}
	for(int i = 0; i < (int)nxtstuff.size(); i++){
		die[i].push_back(nxtstuff[i]);
		dnc(die[i]);
	}
}

set <int> adj[1405];
int sz[1405], block[1405], up[1405];
vector <pi> what;
void comp(int x, int par){
	sz[x] = 1;
	up[x] = par;
	for(auto i : adj[x])if(i != par && !block[i])comp(i, x), sz[x] += sz[i];
	what.push_back({sz[x], x});
}

void Detect(int T, int N) {
	if(T == 1){
		for(int i = 0; i < N; i++){
			for(int j = i + 1; j < N; j++){
				Place[i] = Place[j] = 1;
				if(Ask(i, j, Place))Answer(i, j);
				Place[i] = Place[j] = 0;
			}
		}
		return;
	}
	/*
	vector <int> lol;
	for(int i = 0; i < N; i++)lol.push_back(i);
	shuffle(lol.begin(), lol.end(), rng);
	dnc(lol);
	*/
	for(int i = 1; i < N; i++){
		int hd = 0, res = -1;
		for(int j = 0; j < N; j++)block[j] = 0;
		while(1){
			what.clear();
			comp(hd, -1);
			if(sz[hd] == 1){
				break;
			}
			sort(what.begin(), what.end());
			pi bruh = {sz[hd] / 2, 0};
			int tmp = lower_bound(what.begin(), what.end(), bruh) - what.begin();
			if(tmp == (int)what.size())tmp--;
			int fin = (tmp ? (abs(what[tmp].fi - sz[hd] / 2) < abs(what[tmp - 1].fi - sz[hd] / 2) ? tmp : tmp - 1) : tmp);
			fin = what[fin].se;
			for(int a = 0; a < N; a++)Place[a] = 1;
			Place[fin] = 0;
			if(Ask(0, i, Place)){
				//not in subtree
				block[fin] = 1;
			}
			else{
				hd = fin;
				if(up[fin] != -1)block[up[fin]] = 1;
			}
		}
		int repl = -1;
		for(auto j : adj[hd]){
			for(int a = 0; a < N; a++)Place[a] = 1;
			Place[i] = 0;
			if(j && !Ask(0, j, Place))repl = j;
		}
		if(repl != -1){
			adj[repl].erase(hd);
			adj[hd].erase(repl);
			adj[hd].insert(i);
			adj[i].insert(hd);
			adj[i].insert(repl);
			adj[repl].insert(i);
		}
		else adj[hd].insert(i), adj[i].insert(hd);
	}
	for(int i = 0; i < N; i++){
		for(auto j : adj[i]){
			//cout << j << ' ';
			if(j > i)Answer(i, j);
		}
	}
}

Compilation message (stderr)

park.cpp: In function 'void Detect(int, int)':
park.cpp:100:15: warning: unused variable 'res' [-Wunused-variable]
  100 |   int hd = 0, res = -1;
      |               ^~~

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 0 / 27
• Subtask 4: 0 / 30
• Subtask 5: 0 / 23