粉碎糖果

/*
题目思路：
1. 使用Stream API进行数组转换和处理。
2. 扫描整个糖果板，看是否有三个或三个以上相同的糖果在一行或一列。如果找到，标记这些糖果。
3. 把被标记的糖果消除，并让上面的糖果掉下来填补空缺。
4. 重复上述步骤，直到没有更多的糖果可以被消除。
*/
import java.util.Arrays;
 
public class CandyCrushStream {
    public int[][] candyCrush(int[][] board) {
        int rows = board.length;
        int cols = board[0].length;
        boolean[] toCrushRow = new boolean[rows * cols];
        boolean[] toCrushCol = new boolean[rows * cols];
 
        Arrays.stream(board).flatMapToInt(Arrays::stream).forEach(candy -> {
            for (int i = 0; i < rows; i++) {
                for (int j = 0; j < cols - 2; j++) {
                    if (board[i][j] != 0 && board[i][j] == board[i][j + 1] && board[i][j] == board[i][j + 2]) {
                        toCrushRow[i * cols + j] = toCrushRow[i * cols + j + 1] = toCrushRow[i * cols + j + 2] = true;
                    }
                }
            }
            for (int j = 0; j < cols; j++) {
                for (int i = 0; i < rows - 2; i++) {
                    if (board[i][j] != 0 && board[i][j] == board[i + 1][j] && board[i][j] == board[i + 2][j]) {
                        toCrushCol[i * cols + j] = toCrushCol[(i + 1) * cols + j] = toCrushCol[(i + 2) * cols + j] = true;
                    }
                }
            }
        });
 
        boolean toCrush = Arrays.stream(toCrushRow).anyMatch(c -> c) || Arrays.stream(toCrushCol).anyMatch(c -> c);
 
        if (toCrush) {
            for (int j = 0; j < cols; j++) {
                int idx = rows - 1;
                for (int i = rows - 1; i >= 0; i--) {
                    if (!toCrushRow[i * cols + j] && !toCrushCol[i * cols + j]) {
                        board[idx--][j] = board[i][j];
                    }
                }
                while (idx >= 0) {
                    board[idx--][j] = 0;
                }
            }
        }
 
        return toCrush ? candyCrush(board) : board;
    }
}