Problem Statement

You want to walk in a forest but you can only walk the paths where the sum is your lucky

number $($given$).$ You start at a fixed point forming a tree of paths. Don$$t worry atleast one valid

path will always be there.

Eg:

If the tree is $5,4,8,11,$null,$9,4,-7,2,$null,null,$5,1$ which becomes

Here if your lucky number was $22$ you can find three paths $($paths have to be from root to

leaf only$)$:

$5,4,11,2$;$5,8,9$;$5,8,4,5$

Another example:

Input: $1,4,3,$null,null,$-10,$null,$10,2$::$5$

Tree:

lucky number: $5$

Paths: $1,4$;$1,3,-10,11$

Another example:

Input: $1,2,3,4,5,$null,$-4,1$::$0$

Tree:

lucky number: $0$

Paths: $1,3,-4$

Requirements

$1.$ Implement the above problem statement as a DFS$.$

$2.$ Analyze the time complexity of your algorithm.

$3.$ Implement the above problem statement using Python $3\mathrm{.}7.$

$4.$ Make sure proper exception handling is written for the code.