Submission #1262922

#	Time	Username	Problem	Language	Result	Execution time	Memory
1262922		4QT0R	Circle selection (APIO18_circle_selection)	C++20	12 / 100	239 ms	37712 KiB

circle_selection

#include <bits/stdc++.h>
using namespace std;
#define ll long long

ll n;
vector<array<ll, 3>> info;
vector<array<ll, 3>> points;
vector<ll> ans;
vector<bool> on;

ll grid_length;

ll sq(ll x)
{
	return x * x;
}

bool query(ll i, ll j)
{
	return (sq(info[i][0] - info[j][0]) + sq(info[i][1] - info[j][1])) <= sq(info[i][2] + info[j][2]);
}

void remake()
{
	vector<array<ll, 3>> new_points;
	for (auto [x,y,ind] : points)
	{
		if (!on[ind])
			continue;
		new_points.push_back({info[ind][0] / grid_length, info[ind][1] / grid_length, ind});
	}
	swap(points, new_points);
}

int main()
{
	ios_base::sync_with_stdio(0);
	cin.tie(0);

	cin >> n;
	ans.resize(n);
	on.resize(n, 1);
	for (ll i = 1, x, y, r; i <= n; i++)
	{
		cin >> x >> y >> r;
		info.push_back({x, y, r});
	}
	vector<ll> kol(n);
	iota(kol.begin(), kol.end(), 0);
	sort(kol.begin(), kol.end(), [&](ll a, ll b)
		 { return info[a][2] == info[b][2] ? a < b : info[a][2] > info[b][2]; });
	grid_length = info[kol[0]][2];
	for (ll i = 0; i < n; i++)
		points.push_back({info[i][0], info[i][1], i});
	sort(points.begin(), points.end());
	remake();
	for (auto now : kol)
	{
		if (!on[now])
			continue;
		if (2 * info[now][2] <= grid_length)
		{
			grid_length = info[now][2];
			remake();
		}
		ll cur_x = info[now][0] / grid_length;
		ll cur_y = info[now][1] / grid_length;
		auto lst = points.begin();
		auto fin = lower_bound(points.begin(), points.end(), (array<ll, 3>){cur_x + 2, cur_y + 3, -1});
		for (ll x = cur_x - 2; x <= cur_x + 2; x++)
		{
			auto it = lower_bound(lst, fin, (array<ll, 3>){x, cur_y - 2, -1});
			for (; it != fin && ((*it)[0] == x) && ((*it)[1] <= (cur_y + 2)); it++)
			{
				ll ind = (*it)[2];
				if (on[ind] && query(now, ind))
				{
					on[ind] = false;
					ans[ind] = now;
				}
			}
			swap(lst, it);
		}
	}
	for (auto x : ans)
		cout << x + 1 << ' ';
	cout << '\n';
}

• Subtask 1: 0 / 7
• Subtask 2: 12 / 12
• Subtask 3: 0 / 15
• Subtask 4: 0 / 23
• Subtask 5: 0 / 30
• Subtask 6: 0 / 13