Wrap up Exercise - List

Class objectives

List Exercises

Exercise 1: Print common items in two lists

Given two empty lists lst1 and lst2. random.randint(1, 50) generates random numbers from 1 to 50. Randomly add 10 numbers to each empty list, write a function to print common items.

import random

lst1 = []
lst2 = []

def randomly_add_items(lst1, lst2):

def find_common_items(lst1, lst2):

Exercise 2: Remove duplicated items from a list

Given a lst of integers. Write a function to remove duplicated items and return in a new list.

lst = [12, 23, 34, 23, 34, 25, 65, 32, 25]

# Implement this function to return [12,23,34,25,65,32]
def remove_dups(lst):

Exercise 3: Return the sum of list items

Given two lists with the same length of integer items. Write a function to return sum of list items in a new list.

lst1 = [1,2,3,4,5]
lst2 = [2,3,4,5,6]

# Implement the function to return [3,5,7,9,11]
def add_list_items(lst1, lst2):

More on Lists

Most common List functions

Following are some common Python functions to process data. Here it comes to level up in Python lists, do more fun and exciting exercises.

Function name
add object at end
insert(pos, item)
add object anywhere
remove(item), pop()
delete object
reverse in-place , changes original list
sort in-place, changes original list
copy of reversed
copy of sorted
merger another list
number of occurrences
first index of a value
max value of list items
min value of list items

Persumably, list is a box of chocolates in which chocolates in and out. Possible occasions are, chocolates are eaten, new ones are in or they are given to others. Basically, Python offers function to each of those occasions.

append(item): Add a item to the end of the list

lst = [1,2,3,4,5]

print(lst) # returns [1,2,3,4,5,6]

insert(pos, item): Insert a item to a position

lst = [1,2,3,4,5]
lst.insert(2, 6) # insert 6 to index 2

# returns [1,2,6,3,4,5]
# 6 becomes the item at index 2

remove(item) or pop(): Remove a item from the list

lst = [1,2,3,4,5]
lst.remove(3) # remove item 3 from the list
print(lst) # returns [1,2,4,5]

an_item = lst.pop() # return 5
another_item = lst.pop() # return 4
print(lst) # return [1,2]

reverse(): Reverse a list

lst = [1,2,3,4,5]

print(lst) # returns [5,4,3,2,1]

sort(): Sort a list

lst = [3,1,4,2,5]
lst.sort() # sort the list
print(lst) # returns [1,2,3,4,5]

count(item): Counts numbers of this item in the list

lst = [1,2,3,3,4,5,6,6,7,6]
print(lst.count(6)) # returns 3

index(item): Returns the index of the item

lst = [1,2,3,4,5]
print(lst.index(4)) # returns 3

max(lst): Returns the max value of list items

lst = [12,34,432435,54,62,3232]
print(max(lst)) # returns 432435

max(lst): Returns the min value of list items

lst = [12,34,432435,54,62,3232]
print(min(lst)) # returns 12


Given a unsorted list of integers. Write a function to return the biggest item.

lst = [13,42,23,543,23,54,134]
def return_max(lst): # returns 543

  • Not allowed to use max(lst) function
  • Not necessary to sort the list
  • You are encouraged to solve the problem with algorithm(which basically means using loops, conditionals and mathmatical operations)
  • Assume a random number A is the biggest number and loop through the list to find bigger the one one than A