地上有一个m行和n列的方格。一个机器人从坐标0,0的格子开始移动，每一次只能向左，右，上，下四个方向移动一格，但是不能进入行坐标和列坐标的数位之和大于k的格子。 例如，当k为18时，机器人能够进入方格

Posted 2021-12-28 q-1993

public class Solution 
    public int movingCount(int threshold, int rows, int cols)
    
        if(threshold < 0 || rows < 0 || cols < 0)
            return 0;
        
       
        boolean[] visited = new boolean[rows*cols];
       // for(int row = 0; row < rows; row++)
        //    for(int col = 0; col < cols; col++)
        //        if( movingCountCore(threshold,row,rows,,col,cols,visited))
        //            
        //        
       //     
       // 
        
        int count = movingCountCore(threshold,0,rows,0,cols,visited);
        return count;
    
   
    public static int movingCountCore(int threshold, int row,int rows, int col, int cols,boolean[] visited)
        
        int res = 0;
        if(row>=0 && row<rows && col>=0 && col<cols && visited[row*cols+col]==false)
            if(splitNum(row) + splitNum(col) <= threshold)
                visited[row*cols+col]=true;
                res = 1+movingCountCore(threshold,row+1,rows, col,cols,visited)
                    +movingCountCore(threshold,row-1,rows, col,cols,visited)
                    +movingCountCore(threshold,row,rows, col+1,cols,visited)
                    +movingCountCore(threshold,row,rows, col-1,cols,visited);
            
            
        
        return res;
        
    
    public static int splitNum(int number)
        int sum = 0;
        while(number >0)
            sum+=number%10;
            number =  number/10;
        
        return sum;