Questions solved:
three-way-partitioning

two pointer approach.

left=left-1 increment only if find do same for right .

As I am going to begin with LinkedList: Wanted to freshen up on OOPS concept(has been a long time since last used it)

rotate-string

Beautiful Solution :
len(s)==len(goal) and goal in s+s

0(n) possible through KMP (not learned yet)

`species='mammal'

class Dog():
def init(self,breed,name):
self.breed=breed
self.name=name

1. init can be thought as constructor for the class
2. it will be called automatically when u create instance of a class
3. self->represents as instance of the object itself.
4. attribute
5. we take in the argument
6. assign it using self.attrivute_name
7. operations/acitons----->method is a fn that is inside of class that will work with object in some waydef bark(self,number): print("WOOF! my name is {} and my number is {}".format(self.name,number))

my_dog=Dog('lab','Frankie')

notice this we are getting an error as we havent given any positional argument

because we are expecting breed parameter

so lets pass one

notice that attributes , never have () that because attributes it not something you execu

it is something you call back

print(my_dog.breed,my_dog.name)

my_dog.bark(10)

called method

class circle:
#clas sobject attribute

def __init__(self):    self.pi=3.15def circumference(self,radius):        return radius*self.pi*2

C=circle()
C.circumference(2)`