剑指offer 机器人的运动范围

class Solution {
public:
	int movingCount(int threshold, int rows, int cols)
	{
		bool* visited = new bool[rows*cols];
		memset(visited, 0, rows*cols);
		int count = movingCountCore(threshold, rows, cols, 0, 0, visited);
		delete[]visited;
		return count;
	}
	int movingCountCore(int threshold, int rows, int cols, int row, int col, bool* visited)
	{
		int count = 0;
		if (check(threshold, rows, cols, row, col, visited))
		{
			visited[row*cols + col] = true;
			count = 1 + movingCountCore(threshold, rows, cols, row, col - 1, visited) +
				movingCountCore(threshold, rows, cols, row - 1, col, visited) +
				movingCountCore(threshold, rows, cols, row, col + 1, visited) +
				movingCountCore(threshold, rows, cols, row + 1, col, visited);
		}
		return count;
	}
 
	/*该函数检查坐标为(row,col)的方格能够进入*/
	bool check(int threshold, int rows, int cols, int row, int col, bool*visited)
	{
		if (row >= 0 && row < rows&&col >= 0 && col < cols
			&&getDigitSum(row) + getDigitSum(col) <= threshold 
			&& !visited[row*cols + col])
			return true;
		return false;
	}
 
	/*计算一个数的所有位数之和*/
	int getDigitSum(int number)
	{
		int sum = 0;
		while (number > 0)
		{
			sum += number % 10;
			number = number / 10;
		}
		return sum;
	}
};