미세먼지 안녕!

www.acmicpc.net/problem/17144

17144번: 미세먼지 안녕!

#include <iostream>

using namespace std;

int dy[] = { 0,0,1,-1 };
int dx[] = { 1,-1,0,0 };

int r, c, t;
int map[2][50][50];
int up_y, up_x, down_y, down_x;

void spread(int cur) {
	int next = (cur + 1) % 2;
	for (int y = 0; y < r; y++) {
		for (int x = 0; x < c; x++) {
			if (map[cur][y][x] == -1) {
				map[next][y][x] = -1;
			}
			else map[next][y][x] = 0;
		}
	}
	for (int y = 0; y < r; y++) {
		for (int x = 0; x < c; x++) {
			int val = (map[cur][y][x] / 5);
			int candi = 0;
			for (int dir = 0; dir < 4; dir++) {
				int ny = y + dy[dir]; int nx = x + dx[dir];
				if (ny < 0 || ny >= r || nx < 0 || nx >= c) continue;
				if (map[next][ny][nx] != -1) {
					map[next][ny][nx] += val;
					candi += val;
				}
			}
			if (map[next][y][x] != -1) {
				map[next][y][x] += map[cur][y][x] - candi;
			}
		}
	}
}

void move(int cur) {
	for (int y = up_y - 1; y > 0; y--) {
		map[cur][y][0] = map[cur][y - 1][0];
	}
	for (int x = 0; x < c-1; x++) {
		map[cur][0][x] = map[cur][0][x+1];
	}
	for (int y = 0; y < up_y; y++) {
		map[cur][y][c-1] = map[cur][y + 1][c-1];
	}
	for (int x = c-1; x > 1; x--) {
		map[cur][up_y][x] = map[cur][up_y][x-1];
	}
	map[cur][up_y][1] = 0;
	
	for (int y = down_y + 1; y < r - 1; y++) {
		map[cur][y][0] = map[cur][y + 1][0];
	}
	for (int x = 0; x < c - 1; x++) {
		map[cur][r-1][x] = map[cur][r-1][x + 1];
	}
	for (int y = r-1; y > down_y; y--) {
		map[cur][y][c - 1] = map[cur][y - 1][c - 1];
	}
	for (int x = c - 1; x > 1; x--) {
		map[cur][down_y][x] = map[cur][down_y][x - 1];
	}
	map[cur][down_y][1] = 0;
}

int main() {
	ios_base::sync_with_stdio(false);
	cin >> r >> c >> t;
	up_y = -1;
	for (int y = 0; y < r; y++) {
		for (int x = 0; x < c; x++) {
			cin >> map[0][y][x];
			if (map[0][y][x] == -1) {
				if (up_y == -1) {
					up_y = y; up_x = x;
				}
				else {
					down_y = y; down_x = x;
				}
			}
		}
	}
	int cur = 0;
	for (int time = 0; time < t; time++) {
		spread(cur);
		cur = (cur + 1) % 2;
		move(cur);
	}
	int answer = 0;
	for (int y = 0; y < r; y++) {
		for (int x = 0; x < c; x++) {
			if (map[cur][y][x] != -1) {
				answer += map[cur][y][x];
			}
		}
	}
	cout << answer << "\n";
	return 0;
}