private static final int[][] DIRECTIONS = { { -1, 0 }, { 0, 1 }, { 1, 0 }, { 0, -1 } };
private static int[][] grid, tempGrid;
private static int rows, cols;
private static int purifierTop = -1;
public static void main(String[] args) throws IOException {
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
StringTokenizer st = new StringTokenizer(br.readLine());
rows = Integer.parseInt(st.nextToken());
cols = Integer.parseInt(st.nextToken());
int time = Integer.parseInt(st.nextToken());
grid = new int[rows][cols];
tempGrid = new int[rows][cols];
for (int i = 0; i < rows; i++) {
st = new StringTokenizer(br.readLine());
for (int j = 0; j < cols; j++) {
int value = Integer.parseInt(st.nextToken());
if (j == 0 && purifierTop == -1 && value == -1) {
purifierTop = i;
}
grid[i][j] = value;
}
}
for (int turn = 1; turn <= time; turn++) {
for (int[] arr : tempGrid) {
Arrays.fill(arr, 0);
}
spreadDust();
swapGrids();
circulateAir();
}
System.out.println(getTotalDust());
}
private static void swapGrids() {
int[][] temp = tempGrid;
tempGrid = grid;
grid = temp;
}
private static void spreadDust() {
for (int i = 0; i < rows; i++) {
for (int j = 0; j < cols; j++) {
spreadFromCell(i, j);
}
}
}
private static void spreadFromCell(int row, int col) {
int value = grid[row][col];
if (value == -1)
tempGrid[row][col] = -1;
if (value <= 0)
return;
int spreadAmount = value / 5;
if (spreadAmount > 0) {
for (int[] direction : DIRECTIONS) {
int newRow = row + direction[0];
int newCol = col + direction[1];
if (isValidPosition(newRow, newCol) && grid[newRow][newCol] != -1) {
value -= spreadAmount;
tempGrid[newRow][newCol] += spreadAmount;
}
}
}
tempGrid[row][col] += value;
}
private static void circulateAir() {
int[] state = { purifierTop, 1, grid[purifierTop][1] };
grid[purifierTop][1] = 0;
for (int direction = 1, count = 0; count < 4; direction = (direction + 3) % 4, count++) {
circulateAirInLine(state, direction);
}
state = new int[] { purifierTop + 1, 1, grid[purifierTop + 1][1] };
grid[purifierTop + 1][1] = 0;
for (int direction = 1, count = 0; count < 4; direction = (direction + 1) % 4, count++) {
circulateAirInLine(state, direction);
}
}
private static void circulateAirInLine(int[] state, int direction) {
while (true) {
int newRow = state[0] + DIRECTIONS[direction][0];
int newCol = state[1] + DIRECTIONS[direction][1];
if (!isValidPosition(newRow, newCol) || grid[newRow][newCol] == -1)
break;
int tempValue = grid[newRow][newCol];
grid[newRow][newCol] = state[2];
state[0] = newRow;
state[1] = newCol;
state[2] = tempValue;
}
}
private static boolean isValidPosition(int row, int col) {
return row >= 0 && col >= 0 && row < rows && col < cols;
}
private static int getTotalDust() {
int totalDust = 0;
for (int i = 0; i < rows; i++) {
for (int j = 0; j < cols; j++) {
if (grid[i][j] != -1) {
totalDust += grid[i][j];
}
}
}
return totalDust;
}
출처:https://www.acmicpc.net/problem/17144
