algo

Question 1

python: To declare a variable without assigning it a value, type

Answer 1

my_variable = None

Question 2

algo: For a linked list, the main 2 attributes you need are

Answer 2

data and next

Question 3

python: To make the most basic class, type

Answer 3

class MyClass:
    pass

Question 4

python: Every file that you create is a

Answer 4

library

Question 5

python: To import one specific class from an external file, type

Answer 5

from library_name import ClassName

Question 6

python: To turn two lists into a dictionary, type

Answer 6

dict(zip(list1, list2))

Question 7

python: To slice the last 8 characters from a string, type

Answer 7

my_string[-8:]

Question 8

python: To round a number to the nearest whole number, type

Answer 8

round(1.3)

Question 9

python: To make a one line if else statement, type

Answer 9

“true value” if 10==10 else “false_value”

Question 10

python: To make a node of a linked list that takes in its data upon instantiation, type

Answer 10

class Node:
    data = None
    next = None
    def \_\_init\_\_(self, data):
      self.data = data

Question 11

python: To call a class method on the class itself, type

Answer 11

ClassName.method_name(class_instance)

Question 12

python: To import a class called MyClass from a file called my_file.py in the current directory, type

Answer 12

from my_file import MyClass

Question 13

python: All class methods must have a

Answer 13

self argument

Question 14

python: To call a class variable from inside a class method, type

Answer 14

self.variable_name

Question 15

python: To call a class method from inside another class method, type

Answer 15

self.method_name()

Question 16

python: To set a default value for a function, type

Answer 16

def my_function(param1, param2 = True):
    return param1

note: Params with default value must all come at the end

Question 17

python: To pass in unlimited named parameters into a function, type

Answer 17

def my_function(**kwargs):
    return ...

my_function(param1 = “string”, param2 = “string”):

Note: All the params will be accessible in a dict called kwargs.
Note: The **kwargs arguments must come at the end.

Question 18

python: To create a class where the __init__ function sets all the keyword arguments as attributes, type

Answer 18

class MyClass:
def __init__(self, **kwargs):
for key, value in kwargs.items():
setattr(self, key, value)

Question 19

algo: Usually, your algorithm with use a

Answer 19

while True loop instead of a for loop, will use break, pass for logic inside. Afterwards try to replace while True: with like while pointer > 4:

Question 20

python: Attributes in a class that are declared as attribute_name = “string” but not explicitly set using self.attribute_name in the __init__ method or any other method are

Answer 20

universal and all the instances can at once have their attribute values changed using MyClass.attribute_name = “string”

Question 21

python: To inherit a class, type

Answer 21

class MyClass(ParentClass):
    pass

Question 22

algo: For efficiency, avoid

Answer 22

nested loops

Question 23

algo: The purpose of big 0 notation is

Answer 23

to assess how much time an algorithm will take to run and how much space it will take in memory, as the input gets arbitrarily larger

Question 24

algo: The main big 0 notations are

Answer 24

0(n) = Linear - one loop
0(1) = Static - no loops
0(n^2) = Quadratic - One nested loop

Question 25

algo: For big 0 notation, people usually want to know

Answer 25

the worst case scenario

Question 26

algo: In general, the the most efficient

Answer 26

functions are the built in ones

Question 27

algo: Hash tables and lists run in

Answer 27

constant time

Question 28

python: The two ways to create a generator are

Answer 28

(item*item for item in my_list)

or

def my_generator(my_list):
    for item in my_list:
        yield item*item

The generator become and iterable which you can then use a for loop on, or return where the pointer currrently is by running next(my_generator) and the pointer will move to the next index.

Question 29

python: To call a lambda function, type

Answer 29

my_function = lambda param1 : param1 *param1

my_function(2)

Note: Lambda functions are mostly used to run a one line function as a parameter into another function to save space.

Question 30

python: If you are not sure if a parameter is the right type, the pythonic approach is

Answer 30

duck typing. You put the code in a try/except block and assume the parameter is the correct type

try:
except Exception as e:
raise e

Question 31

python: A double linked list is

Answer 31

a list of nodes that are connected forwards using a next attribute and a backwards using the prev attribute