Submission #727199

#	Time	Username	Problem	Language	Result	Execution time	Memory
727199		SanguineChameleon	Hexagonal Territory (APIO21_hexagon)	C++17	20 / 100	710 ms	67816 KiB

hexagon

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

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};

int draw_territory(int N, int A, int B, vector<int> D, vector<int> L) {
	if (N == 3) {
		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) {
		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;
	}
	return 0;
}

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