Submission #727770

#	Time	Username	Problem	Language	Result	Execution time	Memory
727770		SanguineChameleon	Hexagonal Territory (APIO21_hexagon)	C++17	47 / 100	659 ms	106436 KiB

hexagon

#include "hexagon.h"
#include <bits/stdc++.h>
using namespace std;

#ifdef KAMIRULEZ
	const bool local = true;
	const int subtask = 5;
#else
	const bool local = false;
	const int subtask = -1;
#endif

const long long mod = 1e9 + 7;
const long long one_half = (mod + 1) / 2;
const long long one_third = (mod + 1) / 3;
const int dx[7] = {0, 0, 1, 1, 0, -1, -1};
const int dy[7] = {0, 1, 1, 0, -1, -1, 0};

struct point {
	long long x, y;

	point() {};

	point(long long _x, long long _y): x(_x), y(_y) {};

	point operator*(long long d) {
		return point(x * d, y * d);
	}

	point operator+(point p2) {
		return point(x + p2.x, y + p2.y);
	}

	long long operator^(point p2) {
		return x * p2.y - y * p2.x;
	}
};

point dv[7] = {point(0, 0), point(0, 1), point(1, 1), point(1, 0), point(0, -1), point(-1, -1), point(-1, 0)};

ostream& operator<<(ostream &out, point p) {
	out << "(" << p.x << "," << p.y << ")";
	return out;
}

struct line {
	int type, dir, len, id;
	point p1, p2;

	line() {};

	line(int _type, int _dir, point _p1, point _p2, int _id): type(_type), dir(_dir), p1(_p1), p2(_p2), id(_id) {
		len = p2.x - p1.x + 1;
	};

	long long calc() {
		long long res = 0;
		long long Ly = p1.y;
		long long Ry = p1.y + (dir == 1 ? 0 : len - 1);
		if (type == 1) {
			Ly = 1 - Ly;
			Ry = 1 - Ry;
		}
		return (Ly + Ry) % mod * len % mod * one_half % mod;
	}

	long long eval_x(long long x) {
		if (dir == 1) {
			return p1.y;
		}
		else {
			return p1.y + (x - p1.x);
		}
	}

	void shorten(long long left_x, long long right_x) {
		long long v1 = eval_x(left_x);
		long long v2 = eval_x(right_x);
		p1 = point(left_x, v1);
		p2 = point(right_x, v2);
	}
};

ostream& operator<<(ostream &out, line L) {
	if (L.type == 1) {
		out << "(bottom,";
	}
	else {
		out << "(top,";
	}
	out << L.p1 << "," << L.p2 << ")";
	return out;
}

bool operator<(line L1, line L2) {
	int max_x = max(L1.p1.x, L2.p1.x);
	int v1 = L1.eval_x(max_x);
	int v2 = L2.eval_x(max_x);
	if (v1 != v2) {
		return v1 < v2;
	}
	else {
		return L1.type < L2.type;
	}
};

struct comp {
	line bottom, top;
	int left_x, right_x, len;

	comp(line _bottom, line _top, int _left_x, int _right_x): bottom(_bottom), top(_top), left_x(_left_x), right_x(_right_x) {
		bottom.shorten(left_x, right_x);
		top.shorten(left_x, right_x);
		len = right_x - left_x + 1;
	}

	long long calc() {
		long long Ly = top.p1.y - bottom.p1.y + 1;
		long long Ry = top.p2.y - bottom.p2.y + 1;
		return (Ly + Ry) % mod * len % mod * one_half % mod;
	}
};

int draw_territory(int N, int A, int B, vector<int> D, vector<int> L) {
	if (N == 3 && (!local || subtask == 1 || subtask == 2)) {
		int len = L[0] + 1;
		long long A_sum = 1LL * len * (len + 1) % mod * one_half % mod;
		long long B_sum = 1LL * len * (len - 1) % mod * one_half % mod + (len - 1) * len % mod * (len * 2 - 1) % mod * one_half % mod * one_third % mod;
		return (A_sum * A + B_sum * B) % mod;
	}
	long long L_sum = 0;
	for (int i = 0; i < N; i++) {
		L_sum += L[i];
	}
	if (L_sum <= 2000 && (!local || subtask == 3)) {
		vector<vector<bool>> border(4069, vector<bool>(4069, false));
		vector<vector<int>> dist(4069, vector<int>(4069, -1));
		int cx = 0;
		int cy = 0;
		for (int i = 0; i < N; i++) {
			for (int j = 0; j < L[i]; j++) {
				cx += dx[D[i]];
				cy += dy[D[i]];
				border[cx + 2023][cy + 2023] = true;
			}
		}
		deque<pair<int, int>> q = {{0, 0}};
		dist[0][0] = -2;
		while (!q.empty()) {
			cx = q.front().first;
			cy = q.front().second;
			q.pop_front();
			for (int d = 1; d <= 6; d++) {
				int nx = cx + dx[d];
				int ny = cy + dy[d];
				if (0 <= nx && nx < 4069 && 0 <= ny && ny < 4069 && !border[nx][ny] && dist[nx][ny] == -1) {
					dist[nx][ny] = -2;
					q.push_back({nx, ny});
				}
			}
		}
		q.push_back({2023, 2023});
		dist[2023][2023] = 0;
		long long res = 0;
		while (!q.empty()) {
			cx = q.front().first;
			cy = q.front().second;
			res += 1LL * B * dist[cx][cy] + A;
			res %= mod;
			q.pop_front();
			for (int d = 1; d <= 6; d++) {
				int nx = cx + dx[d];
				int ny = cy + dy[d];
				if (0 <= nx && nx < 4069 && 0 <= ny && ny < 4069 && dist[nx][ny] == -1) {
					dist[nx][ny] = dist[cx][cy] + 1;
					q.push_back({nx, ny});
				}
			}
		}
		return res;
	}
	long long area = 0;
	point cur = point(0, 0);
	vector<point> poly(N);
	for (int i = 0; i < N; i++) {
		poly[i] = cur;
		cur = cur + (dv[D[i]] * L[i]);
	}
	for (int i = 0; i < N; i++) {
		area += poly[i] ^ poly[(i + 1) % N];
	}
	if (area < 0) {
		reverse(D.begin(), D.end());
		for (int i = 0; i < N; i++) {
			if (D[i] <= 3) {
				D[i] += 3;
			}
			else {
				D[i] -= 3;
			}
		}
		reverse(L.begin(), L.end());
		cur = point(0, 0);
		for (int i = 0; i < N; i++) {
			poly[i] = cur;
			cur = cur + (dv[D[i]] * L[i]);
		}
	}
	vector<line> lines;
	vector<int> prv_x;
	for (int i = 0; i < N; i++) {
		point prv = poly[(i + (N - 1)) % N];
		point cur = poly[i];
		point nxt1 = poly[(i + 1) % N];
		point nxt2 = poly[(i + 2) % N];
		if (cur.x < nxt1.x) {
			point p1 = cur;
			point p2 = nxt1;
			int dir = (cur.y == nxt1.y ? 1 : 2);
			if (prv.x < cur.x) {
				if (dir == 1) {
					p1 = p1 + point(1, 0);
				}
				else {
					p1 = p1 + point(1, 1);
				}
			}
			if (prv.x == cur.x && prv.y < cur.y) {
				if (dir == 1) {
					p1 = p1 + point(1, 0);
				}
				else {
					p1 = p1 + point(1, 1);
				}
			}
			if (nxt1.x == nxt2.x && nxt1.y > nxt2.y) {
				if (dir == 1) {
					p2 = p2 + point(-1, 0);
				}
				else {
					p2 = p2 + point(-1, -1);
				}
			}
			if (p1.x <= p2.x) {
				lines.emplace_back(1, dir, p1, p2, lines.size());
				prv_x.push_back(p1.x);
			}
		}
		if (cur.x > nxt1.x) {
			point p1 = nxt1;
			point p2 = cur;
			int dir = (cur.y == nxt1.y ? 1 : 2);
			if (prv.x > cur.x) {
				if (dir == 1) {
					p2 = p2 + point(-1, 0);
				}
				else {
					p2 = p2 + point(-1, -1);
				}
			}
			if (prv.x == cur.x && prv.y > cur.y) {
				if (dir == 1) {
					p2 = p2 + point(-1, 0);
				}
				else {
					p2 = p2 + point(-1, -1);
				}
			}
			if (nxt1.x == nxt2.x && nxt1.y < nxt2.y) {
				if (dir == 1) {
					p1 = p1 + point(1, 0);
				}
				else {
					p1 = p1 + point(1, 1);
				}
			}
			if (p1.x <= p2.x) {
				lines.emplace_back(2, dir, p1, p2, lines.size());
				prv_x.push_back(p1.x);
			}
		}
	}
	vector<pair<int, pair<int, line>>> events;
	for (auto L: lines) {
		events.push_back({L.p1.x - 1, {2, L}});
		events.push_back({L.p1.x, {0, L}});
		events.push_back({L.p2.x, {1, L}});
	}
	sort(events.begin(), events.end());
	set<line, less<>> S;
	vector<comp> comps;
	for (auto e: events) {
		int cur_x = e.first;
		int type = e.second.first;
		line L = e.second.second;
		auto it = (type == 0 ? S.insert(L).first : S.lower_bound(L));
		if (type == 1) {
			if (it->type == 1 && next(it) != S.end()) {
				auto bottom = it;
				auto top = next(it);
				if (prv_x[bottom->id] <= cur_x && prv_x[top->id] <= cur_x) {
					assert(prv_x[bottom->id] == prv_x[top->id]);
					comps.emplace_back(*bottom, *top, prv_x[bottom->id], cur_x);
					prv_x[bottom->id] = cur_x + 1;
					prv_x[top->id] = cur_x + 1;
				}
			}
			if (it->type == 2 && it != S.begin()) {
				auto bottom = prev(it);
				auto top = it;
				if (prv_x[bottom->id] <= cur_x && prv_x[top->id] <= cur_x) {
					assert(prv_x[bottom->id] == prv_x[top->id]);
					comps.emplace_back(*bottom, *top, prv_x[bottom->id], cur_x);
					prv_x[bottom->id] = cur_x + 1;
					prv_x[top->id] = cur_x + 1;
				}
			}
			S.erase(it);
		}
		if (type == 2) {
			if (it != S.end() && it != S.begin()) {
				auto bottom = prev(it);
				auto top = it;
				if (bottom->type == 1 && top->type == 2) {
					if (prv_x[bottom->id] <= cur_x && prv_x[top->id] <= cur_x) {
						assert(prv_x[bottom->id] == prv_x[top->id]);
						comps.emplace_back(*bottom, *top, prv_x[bottom->id], cur_x);
						prv_x[bottom->id] = cur_x + 1;
						prv_x[top->id] = cur_x + 1;
					}
				}
			}
		}
	}
	if (B == 0 && (!local || subtask == 4 || subtask == 5)) {
		long long res = 0;
		for (auto C: comps) {
			res += C.calc();
			res %= mod;
		}
		if (res < 0) {
			res += mod;
		}
		res = res * A % mod;
		return res;
	}
	return 0;
}

Compilation message (stderr)

hexagon.cpp: In constructor 'line::line(int, int, point, point, int)':
hexagon.cpp:48:12: warning: 'line::p2' will be initialized after [-Wreorder]
   48 |  point p1, p2;
      |            ^~
hexagon.cpp:47:22: warning:   'int line::id' [-Wreorder]
   47 |  int type, dir, len, id;
      |                      ^~
hexagon.cpp:52:2: warning:   when initialized here [-Wreorder]
   52 |  line(int _type, int _dir, point _p1, point _p2, int _id): type(_type), dir(_dir), p1(_p1), p2(_p2), id(_id) {
      |  ^~~~
hexagon.cpp: In member function 'long long int line::calc()':
hexagon.cpp:57:13: warning: unused variable 'res' [-Wunused-variable]
   57 |   long long res = 0;
      |             ^~~

• Subtask 1: 3 / 3
• Subtask 2: 6 / 6
• Subtask 3: 11 / 11
• Subtask 4: 12 / 12
• Subtask 5: 15 / 15
• Subtask 6: 0 / 19
• Subtask 7: 0 / 18
• Subtask 8: 0 / 16