机器人的运动范围

class Solution {
public:
    int count=0；int numSum(int num)
    {
        int rev=0;
        while(num)
        {
            rev+=num%10;
            num=num/10;
        }
        return rev;
    }
    void fun(int x,int y,int threshold,int rows,int cols,bool * flags)
    {
        if(x<0||y<0||x>=rows||y>=cols||flags[x*cols+y])
            return;
        if(flags[x*cols+y]==false&&(numSum(x)+numSum(y)<=threshold) )
        {
            flags[x*cols+y]=true;
            count++;
            fun(x+1,y,threshold,rows,cols,flags);
            fun(x-1,y,threshold,rows,cols,flags);
            fun(x,y+1,threshold,rows,cols,flags);
            fun(x,y-1,threshold,rows,cols,flags);
        }
    }
    int movingCount(int threshold, int rows, int cols)
    {
        bool * flags=new bool[rows*cols];
        for(int i=0;i<rows;i++)
        {
            for(int j=0;j<cols;j++)
                flags[i*cols+j]=false;
        }
        fun(0,0,threshold,rows,cols,flags);
        return count;
    }
};