The $$paint fill$$ or $$floor fill$$ algorithm is implemented in many imageFigure $1($a$)$ shous example of a $89$ array with various cell colors, and Figure $1($b$)$ shows its corresponding

$2D$ array, which is what your program will take as input.

$($a$)$

$($b$)$

Figure $1$: Example of an input $89$ array. $($a$)$ Cell colors. $($b$)$ Input array to program.

Assume that array indices start from $0,$ and the top$-$left cell is $(0,0).$

$($a$)$

$($b$)$

Figure $2$: Example of output $89$ array. $($a$)$ Cell colors. $($b$)$ Output array from program.

editing programs. Given a screen $($represented by a two$-$dimensional array of colors$),$ a point, and a new

color, the algorithm fills in the surrounding area until the color changes from the original color. The $2$D

array is like a graph where the nodes are each cell $($or$,$ pixel$)($i$,$ j$)$ and edges are between adjacent cell $/$

pixel. For example, $($i $+1,$ j$),($i $1,$ j$),($i$,$ j $+1)$ and $($i$,$ j $1).$

You will implement this algorithm in a program to fill connected, similarly colored areas with a different

color. Your algorithm takes as input four parameters: a $2$D array, a start node, a target color, and a

replacement color. The $2$D array$$s elements are colors whose values are $($R$,$G$,$B$,$Y$,$W$,$g$,$X$),$

which refer to $($red$,$ green, blue, yellow, white, grey and black$)$ colors. Start node is given as $($i$,$ j$,$ where i

is a row index and j is a column index.

Figure $1($a$)$ shows example of a $8\backslash$times $9$ array with various cell colors, and Figure $1($b$)$ shows its corresponding

$2$D array, which is what your program will take as input.

Figure $1$: Example of an input $8\backslash$times $9$ array. $($a$)$ Cell colors. $($b$)$ Input array to program.

Assume that array indices start from $0,$ and the top$-$left cell is $(0,0).$

If the start node is $(6,2),$ target color is $$B$($i$.$e$.,$ black$)$ and the replacement color is $$g$($i$.$e$.,$ grey$),$ the

algorithm looks for all nodes in the $2$D array that are connected to the start node by a path of the target

color and changes them to the replacement color. Figure $2($a$)$ shows output of the above input as a $8\backslash$times $9$

array with black cell colors modified to grey. Figure $2($b$)$ is what your program should output for this

input. You should also print a list of cell locations $($i$,$ j$)$ in row major order and the total number of cells

modified. For this input,

$1$

List of cell locations modified:

$(1,6),(1,7),(1,8),$

$(2,6),(2,7),(2,8),$

$(3,7),(3,8),$

$(4,6),(4,7),(4,8),$

$(5,6),(5,7),(5,8),$

$(6,2),(6,7),(6,8),$

$(7,2),(7,3),(7,4),(7,5),(7,6),(7,7),(7,8)$

Number of cells modified: $24$

Figure $2$: Example of output $8\backslash$times $9$ array. $($a$)$ Cell colors. $($b$)$ Output array from program.

You must submit the following to receive full credit.

$(1)$ Python or Java script file with comments and structure.

$(2)$ Testcase$($s$)$ on which you validated your program. Each testcase must be a testcase$-$i$.$txt file where

i $=1,2,...,$ n are indices to your testcase files. You MUST include at least two testcase files.

$(3)$ Please make sure you handle corner cases, and gracefully error out when you are provided with in$-$

correct inputs, etc. Program crashes or errors or no outputs will be penalized.$($a$)$

$($b$)$

Figure $2$: Example of output $89$ array. $($a$)$ Cell colors. $($b$)$ Output array from program.

Give me the correct answer which is asked in the question which satisfies all the requirements and check for corner test cases also?