You are given a $0-$indexed m x n binary matrix land where a $0$ represents a hectare of forested

land and a $1$ represents a hectare of farmland.

To keep the land organized, there are designated rectangular areas of hectares that consist entirely

of farmland. These rectangular areas are called groups. No two groups are adjacent, meaning

farmland in one group is not four$-$directionally adjacent to another farmland in a different group.

land can be represented by a coordinate system where the top left corner of land is $(0,0)$ and

the bottom right corner of land is $($m$-1,$ n$-1).$ Find the coordinates of the top left and bottom

right corner of each group of farmlands. A group of farmlands with a top left corner at $($r$1,$ c$1)$

and a bottom right corner at $($r$2,$ c$2)$ is represented by the $4-$length array $[$r$1,$ c$1,$ r$2,$ c$2].$

Return a $2$D array containing the $4-$length arrays described above for each group of farmlands in

land. If there are no groups of farmlands, return an empty array. You may return the answer in

any order.

Hint:

$1.$ You can use the flood$-$fill algorithm discussed in class to solve this problem.

$2.$ As you are doing DFS for a group of farmlands, you may need to keep track of the maximum

row and column number for the group.