Python
A step by step guide to Python, a language that is easy to pick up yet one of the most powerful.
Introduction
| Name | Preview | Code | Difficulty |
|---|---|---|---|
| Say “Hello, World!” With Python | Get started with Python by printing to stdout. | Python | Easy |
| Python If-Else | Practice using if-else conditional statements! | Python | Easy |
| Arithmetic Operators | Addition, subtraction and multiplication. | Python | Easy |
| Python: Division | Division using future module. | Python | Easy |
| Loops | Practice using “for” and “while” loops in Python. | Python | Easy |
| Write a function | Write a function to check if the given year is leap or not | Python | Medium |
| Print Function | Learn to use print as a function | Python | Easy |
Basic Data Types
| Name | Preview | Code | Difficulty |
|---|---|---|---|
| Lists | Perform different list operations. | Python | Easy |
| Tuples | Learn about tuples and compute hash(T). | Python | Easy |
| List Comprehensions | You will learn about list comprehensions. | Python | Easy |
| Find the Runner-Up Score! | For a given list of numbers, find the second largest number. | Python | Easy |
| Nested Lists | In a classroom of N students, find the student with the second lowest grade. | Python | Easy |
| Finding the percentage | Store a list of students and marks in a dictionary, and find the average marks obtained by a student. | Python | Easy |
Strings
| Name | Preview | Code | Difficulty |
|---|---|---|---|
| sWAP cASE | Swap the letter cases of a given string. | Python | Easy |
| String Split and Join | Use Python’s split and join methods on the input string. | Python | Easy |
| What’s Your Name? | Python string practice: Print your name in the console. | Python | Easy |
| Mutations | Understand immutable vs mutable by making changes to a given string. | Python | Easy |
| Find a string | Find the number of occurrences of a substring in a string. | Python | Easy |
| String Validators | Identify the presence of alphanumeric characters, alphabetical characters, digits, lowercase and uppercase characters in a string. | Python | Easy |
| Text Alignment | Generate the Hackerrank logo with alignments in Python. | Python | Easy |
| Text Wrap | Wrap the given text in a fixed width. | Python | Easy |
| Designer Door Mat | Print a designer door mat. | Python | Easy |
| String Formatting | Print the formatted decimal, octal, hexadecimal, and binary values for $n$ integers. | Python | Easy |
| Alphabet Rangoli | Let’s draw rangoli. | Python | Easy |
| Capitalize! | Capitalize Each Word. | Python | Easy |
| The Minion Game | Given a string, judge the winner of the minion game. | Python | Medium |
| Merge the Tools! | Split a string into subsegments of length $k$, then print each subsegment with any duplicate characters stripped out. | Python | Medium |
Sets
| Name | Preview | Code | Difficulty |
|---|---|---|---|
| Introduction to Sets | Use the set tool to compute the average. | Python | Easy |
| Symmetric Difference | Learn about sets as a data type. | Python | Easy |
| No Idea! | Compute your happiness. | Python | Medium |
| Set .add() | Add elements to set. | Python | Easy |
| Set .discard(), .remove() & .pop() | Different ways to omit set elements. | Python | Easy |
| Set .union() Operation | Use the .union() operator to determine the number of students. | Python | Easy |
| Set .intersection() Operation | Use the .intersection() operator to determine the number of same students in both sets. | Python | Easy |
| Set .difference() Operation | Use the .difference() operator to check the differences between sets. | Python | Easy |
| Set .symmetric_difference() Operation | Making symmetric difference of sets. | Python | Easy |
| Set Mutations | Using various operations, change the content of a set and output the new sum. | Python | Easy |
| The Captain’s Room | Out of a list of room numbers, determine the number of the captain’s room. | Python | Easy |
| Check Subset | Verify if set A is a subset of set B. | Python | Easy |
| Check Strict Superset | Check if A is a strict superset of the other given sets. | Python | Easy |
Math
| Name | Preview | Code | Difficulty |
|---|---|---|---|
| Polar Coordinates | Convert complex numbers to polar coordinates | Python | Easy |
| Find Angle MBC | Find the desired angle in the right triangle. | Python | Medium |
| Triangle Quest 2 | Create a palindromic triangle. | Python | Medium |
| Mod Divmod | Get the quotient and remainder using the divmod operator in Python. | Python | Easy |
| Power - Mod Power | Perform modular exponentiation in Python. | Python | Easy |
| Integers Come In All Sizes | Exercises with big integers in Python. | Python | Easy |
| Triangle Quest | Print a numeric triangle of height N-1 using only 2 lines. | Python | Medium |
Itertools
| Name | Preview | Code | Difficulty |
|---|---|---|---|
| itertools.product() | Find the cartesian product of 2 sets. | Python | Easy |
| itertools.permutations() | Find all permutations of a given size in a given string. | Python | Easy |
| itertools.combinations() | Print all the combinations of a string using itertools. | Python | Easy |
| itertools.combinations_with_replacement() | Find all the combinations of a string with replacements. | Python | Easy |
| Compress the String! | groupby() | Python | Medium |
| Iterables and Iterators | Find the probability using itertools. | Python | Medium |
| Maximize It! | Find the maximum possible value out of the equation provided. | Python | Hard |
Collections
| Name | Preview | Code | Difficulty |
|---|---|---|---|
| collections.Counter() | Use a counter to sum the amount of money earned by the shoe shop owner. | Python | Easy |
| DefaultDict Tutorial | Create dictionary value fields with predefined data types. | Python | Easy |
| Collections.namedtuple() | You need to turn tuples into convenient containers using collections.namedtuple(). | Python | Easy |
| Collections.OrderedDict() | Print a dictionary of items that retains its order. | Python | Easy |
| Word Order | List the number of occurrences of the words in order. | Python | Medium |
| Collections.deque() | Perform multiple operations on a double-ended queue or deque. | Python | Easy |
| Piling Up! | Create a vertical pile of cubes. | Python | Medium |
| Company Logo | Print the number of character occurrences in descending order. | Python | Medium |
Date and Time
| Name | Preview | Code | Difficulty |
|---|---|---|---|
| Calendar Module | Print the day of a given date. | Python | Easy |
| Time Delta | Find the absolute time difference. | Python | Medium |
Errors and Exceptions
| Name | Preview | Code | Difficulty |
|---|---|---|---|
| Exceptions | Handle errors detected during execution. | Python | Easy |
| Incorrect Regex | Check whether the regex is valid or not. | Python | Easy |
Classes
| Name | Preview | Code | Difficulty |
|---|---|---|---|
| Classes: Dealing with Complex Numbers | Create a new data type for complex numbers. | Python | Medium |
| Class 2 - Find the Torsional Angle | Find the angle between two planes. | Python | Easy |
Built-Ins
| Name | Preview | Code | Difficulty |
|---|---|---|---|
| Zipped! | Compute the average by zipping data. | Python | Easy |
| Input() | A Python 2 challenge: Input() is equivalent to eval(raw_input(prompt)). | Python | Easy |
| Python Evaluation | Evaluate the expressions in Python using the expression eval(). | Python | Easy |
| Athlete Sort | Sort the table on the kth attribute. | Python | Medium |
| Any or All | Return True, if any of the iterable is true or if all of it is true using the any() and all() expressions. | Python | Easy |
| ginortS | An uneasy sort. | Python | Medium |
Python Functionals
| Name | Preview | Code | Difficulty |
|---|---|---|---|
| Map and Lambda Function | This challenge covers the basic concept of maps and lambda expressions. | Python | Easy |
| Validating Email Addresses With a Filter | This question covers the concept of filters. | Python | Medium |
| Reduce Function | Python Practice | Python | Medium |
Regex and Parsing
| Name | Preview | Code | Difficulty |
|---|---|---|---|
| Detect Floating Point Number | Validate a floating point number using the regular expression module for Python. | Python | Easy |
| Re.split() | Split the string by the pattern occurrence using the re.split() expression. | Python | Easy |
| Group(), Groups() & Groupdict() | Using group(), groups(), and groupdict(), find the subgroup(s) of the match. | Python | Easy |
| Re.findall() & Re.finditer() | Find all the pattern matches using the expressions re.findall() and re.finditer(). | Python | Easy |
| Re.start() & Re.end() | Find the indices of the start and end of the substring matched by the group. | Python | Easy |
| Regex Substitution | Substitute a string using regex tools. | Python | Medium |
| Validating Roman Numerals | Use regex to validate Roman numerals. | Python | Easy |
| Validating phone numbers | Check whether the given phone number is valid or not. | Python | Easy |
| Validating and Parsing Email Addresses | Print valid email addresses according to the constraints. | Python | Easy |
| Hex Color Code | Validate Hex color codes in CSS. | Python | Easy |
| HTML Parser - Part 1 | Parse HTML tags, attributes and attribute values using HTML Parser. | Python | Easy |
| HTML Parser - Part 2 | Parse HTML comments and data using HTML Parser. | Python | Easy |
| Detect HTML Tags, Attributes and Attribute Values | Parse HTML tags, attributes and attribute values in this challenge. | Python | Easy |
| Validating UID | Validate all the randomly generated user identification numbers according to the constraints. | Python | Easy |
| Validating Credit Card Numbers | Verify whether credit card numbers are valid or not. | Python | Medium |
| Validating Postal Codes | Verify if the postal code is valid or invalid. | Python | Hard |
| Matrix Script | Decode the Matrix. | Python | Hard |
XML
| Name | Preview | Code | Difficulty |
|---|---|---|---|
| XML 1 - Find the Score | Learn about XML parsing in Python. | Python | Easy |
| XML2 - Find the Maximum Depth | Find the maximum depth in an XML document. | Python | Easy |
Closures and Decorators
| Name | Preview | Code | Difficulty |
|---|---|---|---|
| Standardize Mobile Number Using Decorators | Use decorators to standardize mobile numbers. | Python | Easy |
| Decorators 2 - Name Directory | Use decorators to build a name directory. | Python | Easy |
Numpy
| Name | Preview | Code | Difficulty |
|---|---|---|---|
| Arrays | Convert a list to an array using the NumPy package. | Python | Easy |
| Shape and Reshape | Using the shape and reshape tools available in the NumPy module, configure a list according to the guidelines. | Python | Easy |
| Transpose and Flatten | Use the transpose and flatten tools in the NumPy module to manipulate an array. | Python | Easy |
| Concatenate | Use the concatenate function on 2 arrays. | Python | Easy |
| Zeros and Ones | Print an array using the zeros and ones tools in the NumPy module. | Python | Easy |
| Eye and Identity | Create an array using the identity or eye tools from the NumPy module. | Python | Easy |
| Array Mathematics | Perform basic mathematical operations on arrays in NumPy. | Python | Easy |
| Floor, Ceil and Rint | Use the floor, ceil and rint tools of NumPy on the given array. | Python | Easy |
| Sum and Prod | Perform the sum and prod functions of NumPy on the given 2-D array. | Python | Easy |
| Min and Max | Use the min and max tools of NumPy on the given 2-D array. | Python | Easy |
| Mean, Var, and Std | Use the mean, var and std tools in NumPy on the given 2-D array. | Python | Easy |
| Dot and Cross | Use NumPy to find the dot and cross products of arrays. | Python | Easy |
| Inner and Outer | Use NumPy to find the inner and outer product of arrays. | Python | Easy |
| Polynomials | Given the coefficients, use polynomials in NumPy. | Python | Easy |
| Linear Algebra | NumPy routines for linear algebra calculations. | Python | Easy |
Debugging
| Name | Preview | Code | Difficulty |
|---|---|---|---|
| Words Score | Calculate the total score of the list of words. | Python | Medium |
| Default Arguments | Debug a function which uses a default value for one of its arguments. | Python | Medium |