Submission #1035408

#	Time	Username	Problem	Language	Result	Execution time	Memory
1035408		Gray	Counting Mushrooms (IOI20_mushrooms)	C++17	0 / 100	1 ms	344 KiB

mushrooms

#include "mushrooms.h"

#define ff first
#define ss second
#define ll int
#define ln "\n"

using namespace std;

int _qry=200;

int count_mushrooms(int n) {
	std::vector<int> query;
	vector<int> as, bs;
	as.push_back(0);
	int cqry=_qry;
	for (ll i=1; i<=min(2, n-1); i++){
		query = {0, int(i)};
		ll ret = use_machine(query);
		if (ret==0) as.push_back(i);
		else bs.push_back(i);
	}
	for (ll i=3; i<min(cqry+1, n); i+=2){
		if (i+1<min(cqry+1, n)){
			if (as.size()>bs.size()){
				query = {i, as[0], i+1, as[1]};
				ll ret = use_machine(query);
				if (ret==0){
					as.push_back(i);
					as.push_back(i+1);
				}else if (ret==1){
					as.push_back(i+1);
					bs.push_back(i);
				}else if (ret==2){
					as.push_back(i);
					bs.push_back(i+1);
				}else{
					bs.push_back(i);
					bs.push_back(i+1);
				}
			}else{
				query = {i, bs[0], i+1, bs[1]};
				ll ret = use_machine(query);
				if (ret==0){
					bs.push_back(i);
					bs.push_back(i+1);
				}else if (ret==1){
					bs.push_back(i+1);
					as.push_back(i);
				}else if (ret==2){
					bs.push_back(i);
					as.push_back(i+1);
				}else{
					as.push_back(i);
					as.push_back(i+1);
				}
			}
		}else{
			query = {0, (int)i};
			ll ret = use_machine(query);
			if (ret==0) as.push_back(i);
			else bs.push_back(i);
		}
		if (as.size()>100) {
			cqry=i; break;
		}
	}
	


	ll ans=(ll)as.size();
	if (as.size()>bs.size()){
		for (ll i=min(cqry+1, n); i<n; i+=as.size()){
			query.clear();
			for (ll j=0; j<(ll)as.size() and i+j<n; j++){
				query.push_back(as[j]);
				query.push_back(i+j);
			}
			ll ret = use_machine(query);
			if (ret%2==0) ans++;
			ans+=(query.size()-2)/2-ret/2;
		}
	}else{
		for (ll i=min(cqry+1, n); i<n; i+=bs.size()){
			query.clear();
			for (ll j=0; j<(ll)bs.size() and i+j<n; j++){
				query.push_back(bs[j]);
				query.push_back(i+j);
			}
			ll ret = use_machine(query);
			if (ret%2) ans++;
			ans+=ret/2;
		}
	}
	return ans;
}

• Subtask 1: 0 / 100