# Leetcode 807 - Max Increase to Keep City Skyline

`Note:`

- For each cell, find its
`maxRow`

and`maxCol`

. - The new val should be
`min(maxrow, maxcol)`

.

`Question:`

There is a city composed of `n x n`

blocks, where each block contains a single building shaped like a vertical square prism. You are given a 0-indexed `n x n`

integer matrix `grid`

where `grid[r][c]`

represents the height of the building located in the block at row `r`

and column `c`

.

A city’s skyline is the the outer contour formed by all the building when viewing the side of the city from a distance. The skyline from each cardinal direction north, east, south, and west may be different.

We are allowed to increase the height of any number of buildings by `any amount (the amount`

can be different per building). The height of a 0-height building can also be increased. However, increasing the height of a building should not affect the city’s `skyline`

from any cardinal direction.

Return the `maximum total sum`

that the height of the buildings can be increased by without changing the city’s `skyline`

from any cardinal direction.

`Example:`

1 | Input: grid = [[3,0,8,4],[2,4,5,7],[9,2,6,3],[0,3,1,0]] |

`Code:`

1 | /** |