剑指offer_25_机器人的运动范围

public int movingCount(int threshold,int rows ,int cols) {
    boolean[] visted = new boolean[rows * cols];
    for (int i = 0; i < visted.length; i++) {
        // 用这个数组来判断机器人是否经过了某个位置
        visted[i] = false;
    }
    // 获取机器人最多可到达的位置
    int count = movingCountCore(threshold,rows,cols,0,0,visted);
    return count;
}

private int movingCountCore(int threshold, int rows, int cols, int row, int col, boolean[] visted) {
    int count = 0;
    if (check(threshold,rows,cols,row,col,visted)) {
        // 判断符合条件后，将该位置标记为已经来过
        visted[rows * cols + col] = true; // 代表访问过了的
        // 向上下左右四个位置探索
        count = 1 +
                movingCountCore(threshold, rows , cols, row - 1, col, visted) +
                movingCountCore(threshold, rows, cols, row, col - 1, visted) +
                movingCountCore(threshold, rows, cols, row + 1, col, visted) +
                movingCountCore(threshold, rows, cols, row, col + 1, visted);
    }
    return count;
}

private boolean check(int threshold, int rows, int cols, int row, int col, boolean[] visted) {
    // 判断是否越界啦 判断和是否大于阀值
    if (row >=0 && row < rows && col >= 0 && col < cols &&  (getDigitSum(row) + getDigitSum(col) <= threshold) && !visted[row * cols + col])
        return true;
    return false;
}
// 求坐标的和
private int getDigitSum(int row) {
    int sum = 0;
    while (row > 0) {
        sum += row % 10;
        row /= 10;
    }
    return sum;
}