cracking-the-coding-interview

Data Structures and algorithm
How to Merge Strings Alternately?

How to Merge Strings Alternately?

5 minutes

Learn how to merge strings alternately in Python. Explore efficient algorithms and examples to combine two strings by alternating their characters, handling different string lengths.

Data Structures and algorithm
Find Intersection of Two Arrays

Find Intersection of Two Arrays

5 minutes

Learn how to find the intersection of two arrays in Python. Discover efficient algorithms and code examples to solve the common elements problem.

Data Structures and algorithm
Determine if a 9x9 Sudoku Board is Valid

Determine if a 9x9 Sudoku Board is Valid

5 minutes

Learn how to determine if a 9x9 Sudoku board is valid in Python. Explore efficient algorithms and Python code examples to check for row, column, and sub grid uniqueness in a Sudoku puzzle.

Data Structures and algorithm
Check if the given Linked List is Palindrome

Check if the given Linked List is Palindrome

5 minutes

Learn how to check if a linked list is a palindrome with simple steps. Understand linked lists, find the middle, reverse, compare nodes, and solve efficiently.

Data Structures and algorithm
Remove Duplicates from a Sorted Array: Techniques, Examples, and Efficient Solutions

Remove Duplicates from a Sorted Array: Techniques, Examples, and Efficient Solutions

5 minutes

Learn how to remove duplicates from a sorted array in Python. Explore efficient algorithms to eliminate duplicate elements while maintaining the sorted order.

Python
Spiral Matrix in Python

Spiral Matrix in Python

5 minutes

Solve the Spiral Matrix problem in Python. Learn algorithms to traverse a matrix in a spiral order with Python code and detailed explanations for optimal solutions.

Data Structures and algorithm
Valid Palindrome in Python

Valid Palindrome in Python

5 minutes

Learn how to solve the Valid Palindrome in Python. Discover Python examples to check if a string is a palindrome, ignoring spaces, punctuation, and case sensitivity.

Data Structures and algorithm
Reverse a String in Python

Reverse a String in Python

5 minutes

Learn how to reverse a string in Python with efficient algorithms. Explore step-by-step solutions and Python code examples for reversing strings, from simple to advanced methods.

Data Structures and algorithm
Range Sum of BST

Range Sum of BST

5 minutes

Learn how to solve the Range Sum of BST problem in simple steps. Explore BST traversal, sum node values in a range, and optimize tree algorithms efficiently.

FAANG interview questions
Cracking FAANG Coding Interviews

Cracking FAANG Coding Interviews

5 minutes

Prepare for FAANG interviews with practical coding challenges. Master data structures, algorithms, and problem-solving techniques to crack interviews at top tech companies.

Data Structures and algorithm
3Sum in Python

3Sum in Python

5 minutes

Solve the "3Sum" problem in Python. Learn efficient algorithms and step-by-step code examples to find all unique triplets in an array that sum to zero using Python.

Data Structures and algorithm
Find Middle of the Linked List

Find Middle of the Linked List

5 minutes

Learn how to find the middle of a linked list using the two-pointer technique. Simple steps to identify the middle node in odd and even-sized linked lists.

Data Structures and algorithm
Finding the Single Number in an Array

Finding the Single Number in an Array

5 minutes

Learn how to find the single number in an array in Python. Explore efficient algorithms examples to identify the unique element in an array where every other number appears twice.

Data Structures and algorithm
How to Rotate an Array in Python

How to Rotate an Array in Python

5 minutes

Learn how to rotate an array in Python. Explore algorithms and step-by-step Python code examples to rotate arrays by a given number of positions, both left and right.

Data Structures and algorithm
Plus One to a Number

Plus One to a Number

5 minutes

Learn how to add one to a number represented as an array of digits in Python. Explore efficient algorithms and step-by-step Python code examples to solve the "Plus One" problem with arrays.

Data Structures and algorithm
Find Duplicate Elements in an Array

Find Duplicate Elements in an Array

5 minutes

Learn how to find duplicate elements in an array in Python. Discover efficient algorithms to identify and remove duplicates from an array using Python.

Data Structures and algorithm
Longest Substring Without Repeating Character

Longest Substring Without Repeating Character

5 minutes

Explore the longest substring without repeating character in Python. Explore algorithms to find the longest unique substring in a string without duplicates.

Python
Delete Node in a Linked List

Delete Node in a Linked List

5 minutes

Learn how to delete a node in a linked list efficiently in Python. Explore linked list operations, dynamic memory, and coding interview techniques.

Data Structures and algorithm
Product of Array Except Self in Python

Product of Array Except Self in Python

5 minutes

Learn how to solve the "Product of Array Except Self" problem in Python. Discover Python code examples to calculate the product of array elements.

Data Structures and algorithm
Longest Consecutive Sequence in Python

Longest Consecutive Sequence in Python

5 minutes

Solve the Longest Consecutive Sequence problem in Python. Learn how to find the longest sequence of consecutive numbers using efficient Python algorithms.

Data Structures and algorithm
Longest Common Prefix

Longest Common Prefix

5 minutes

Discover the "Longest Common Prefix" problem with this guide. Learn efficient algorithms, and Python code examples to find the longest common prefix of strings.

Data Structures and algorithm
Detect a Cycle in Linked List

Detect a Cycle in Linked List

5 minutes

Learn how to detect a cycle in a linked list using the slow and fast pointer technique. Simple steps to check loops, avoid errors, and solve linked list problems.

Data Structures and algorithm
Greatest Common Divisor of Strings

Greatest Common Divisor of Strings

5 minutes

Discover how to find the Greatest Common Divisor (GCD) of strings in Python. Learn efficient algorithms and examples to determine the largest string that can divide two given strings.

Data Structures and algorithm
Best Time to Buy and Sell Stock

Best Time to Buy and Sell Stock

5 minutes

Learn the best time to buy and sell stock with Python. Discover efficient algorithm examples to solve the "Best Time to Buy and Sell Stock" problem and maximize profit.

Data Structures and algorithm
Move All Zeroes to the End of an Array

Move All Zeroes to the End of an Array

5 minutes

Learn how to move all zeroes to the end of an array in Python. Discover efficient algorithms and step-by-step code examples to solve this common array manipulation problem.

Python Interview Questions
50 Latest Python Interview Questions in 2025

50 Latest Python Interview Questions in 2025

5 minutes

Ace your Python interviews. Covering Python interview questions, data structures, memory management, PEP8, OOP, functions, and more. Learn Python programming skills and succeed in job interviews!

Data Structures and algorithm
Check for Balanced Parentheses

Check for Balanced Parentheses

5 minutes

Learn how to check for balanced parentheses using a stack. Step-by-step guide to validate bracket pairs like (), {}, and [] in strings with simple logic.

Data Structures and algorithm
How to Reverse a Linked List in Python

How to Reverse a Linked List in Python

5 minutes

Learn how to reverse a linked list in Python with our easy tutorial. Explore step-by-step algorithms, and best practices to solve reverse linked list problem in Python.

Data Structures and algorithm
First Missing Positive in Python

First Missing Positive in Python

5 minutes

Learn how to solve the First Missing Positive problem in Python. Discover step-by-step code examples to find the smallest missing positive integer in an unsorted array.

Data Structures and algorithm
Sliding Window Maximum in Python

Sliding Window Maximum in Python

5 minutes

Learn the Sliding Window Maximum problem in Python. Learn efficient techniques to find the maximum element in a sliding window using Python algorithms.

Data Structures and algorithm
Valid Anagram in Python

Valid Anagram in Python

5 minutes

Learn how to solve the "Valid Anagram" problem. Discover algorithms and Python examples to check if two strings are anagrams by comparing their character frequencies.

Data Structures and algorithm
Kids with the Greatest Number of Candies

Kids with the Greatest Number of Candies

5 minutes

Find the solution to the "Kids with the Greatest Number of Candies" problem in Python. Learn how to efficiently determine which kids can have the most candies based on their current count.

Data Structures and algorithm
Merge Two Sorted Lists

Merge Two Sorted Lists

5 minutes

Learn how to merge two sorted lists with our step-by-step guide. Discover efficient algorithms, and solution of merge two sorted linked list in Python.

Data Structures and algorithm
How to Delete Middle Element from a Stack

How to Delete Middle Element from a Stack

5 minutes

Learn how to delete the middle element from a stack with simple steps. Step-by-step guide to solve stack problems using recursion and stack operations.

Data Structures and algorithm
Two Sum Problem

Two Sum Problem

5 minutes

Explore the "Two Sum" problem with this complete guide in Python. Learn efficient algorithms, step-by-step solutions, and Python code examples to find two numbers that add up to a target sum.

Python
Minimum Window Substring in Python

Minimum Window Substring in Python

5 minutes

Learn how to solve the Minimum Window Substring problem in Python. Find the smallest substring that contains all characters using Python algorithms.

Python
Container with Most Water in Python

Container with Most Water in Python

5 minutes

Learn the "Container with Most Water" problem in Python. Learn efficient solutions and algorithms to maximize water container area using Python code examples.

Data Structures and algorithm
Longest Palindromic Substring

Longest Palindromic Substring

5 minutes

Solve the Longest Palindromic Substring problem in Python. Learn step-by-step code examples to find the longest palindrome within a string using Python.