问增加最大值以保持Java的城市天际线

EN

Example:
Input: grid = [[3,0,8,4],[2,4,5,7],[9,2,6,3],[0,3,1,0]]
Output: 35
Explanation: 
The grid is:
[ [3, 0, 8, 4], 
  [2, 4, 5, 7],
  [9, 2, 6, 3],
  [0, 3, 1, 0] ]

The skyline viewed from top or bottom is: [9, 4, 8, 7]
The skyline viewed from left or right is: [8, 7, 9, 3]

The grid after increasing the height of buildings without affecting skylines is:

gridNew = [ [8, 4, 8, 7],
            [7, 4, 7, 7],
            [9, 4, 8, 7],
            [3, 3, 3, 3] ]

Notes:

class Solution {
    public int maxIncreaseKeepingSkyline(int[][] grid) {

        int nrows = grid.length;
        int ncols = grid[0].length;

        int [] leftRig = new int[nrows];
        int [] topBot = new int[ncols];

        //Filling topBot
        for( int i = 0; i < ncols; i++ )
        {
               int max = Integer.MIN_VALUE;    

                for( int j = 0; j < nrows; j++ )
               {
                   if( max <= grid[j][i] )
                       max = grid[j][i];
               }
            topBot[i] = max;
        }

        //Filling leftRig
        for( int k = 0; k < nrows; k++ )
        {
               int max = Integer.MIN_VALUE;    

                for( int l = 0; l < ncols; l++ )
               {
                   if( max <= grid[k][l] )
                       max = grid[k][l];
               }
            leftRig[k] = max;
        }

        int count = 0;
        int min = 0;

        //Enumerating the minimum height to be added
        for( int i = 0; i < nrows; i++ )
        {       
          for( int j = 0; j < ncols; j++ )
            {
                  min = Math.min(leftRig[i],topBot[j]);
                  count += min - grid[i][j];
            }
        }

        return count;
    }
}