Master Coding Interview Problems

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Total questions with solutions: 68

• Every week, I send out 4-6 programming problems with detailed solutions, test cases, and program analysis, all in Go.
• The goal is to help you get good at algorithms and data structures so that you can prepare better for your next coding interviews.

Table of Contents

• Interview Cake
  • Array and string manipulation
    • Merge meeting times
    • Reverse string in place
    • Reverse words
    • Merge sorted arrays
    • Single riffle shuffle
  • Hashing and hash tables
    • In-flight entertainment
    • Permutation palindrome
    • Word cloud data
    • Top scores
    • Find duplicate files
  • Greedy algorithms
    • Apple stocks
    • Highest product of three
    • Product of all other numbers
    • In-place shuffle
  • Sorting, searching, and logarithms
    • Find rotation point
    • Find repeat
  • Trees and graphs
    • Balanced binary tree
    • Binary search tree checker
    • 2nd largest item in a binary search tree
    • Graph coloring
    • MeshMessage
  • Dynamic programming and recursion
    • Recursive string permutations
    • Compute nth Fibonacci number
    • Making change
    • The cake thief
  • Queues and stacks
    • Largest stack
    • A queue with two stacks
    • Parenthesis matching
    • Bracket validator
  • Linked lists
    • Delete node
    • Linked list has a cycle
    • Reverse a linked list
    • Kth to last node
  • General programming
    • Rectangular love
    • Temperature tracker
  • Bit manipulation
    • The stolen breakfast drone
  • Combinatorics, probability, and other math
    • Which appears twice
    • Find in ordered set
    • Simulate 5-sided die
    • Simulate 7-sided die
    • Two egg problem
  • TODO: System Design
• Practical Algorithms and Data Structures
• LeetCode
  • Array/String
    • Two sum I
    • Two sum II
    • Valid palindrome
    • Implement strstr()
    • Reverse words in string
    • String to integer
    • Valid number
    • Longest substring without repeating characters
      • TODO: read more about sliding windows problem here
    • Missing ranges
    • One edit distance
    • Read n characters given Read4
  • Math
    • Reverse integer
    • Plus one
    • Palindrome number
  • Linked list
    • Merge sorted linked list
    • Add two numbers
    • Swap nodes in pairs
    • Merge k sorted linked list
    • Copy list with random pointer
  • Binary tree
    • Validate binary search tree
    • Maximum depth of binary tree
    • Minimum depth of binary tree
    • Balanced binary tree
    • Convert sorted array to balanced binary search tree
    • Convert sorted linked list to balanced binary search tree
    • Binary tree maximum path sum
    • Binary tree upside down
  • Bit manipulation
    • Single number I
    • Single number II
  • Misc
    • Spiral matrix
    • Integer to roman
    • Roman to integer
    • Clone graph
  • Stack
    • Min stack
    • Evaluate reverse polish notation
    • Valid parenthesis
  • Dynamic programming
    • Climbing stairs
    • Unique paths
    • Maximum sum subarray
    • Maximum product max array
    • Coins in a line
  • Binary search
    • Search insert position
    • Find minimum in sorted rotated array
• Cracking the Coding Interviews
  • Bit manipulation
    • Bit operation
    • Bit insertion
• Elements of Programming Interviews
• Grokking the Coding Interview: Patterns for Coding Questions
  • Sliding Window
    • Average of any contiguous subarray of size k
    • Maximum sum of any contiguous subarray of size k
    • Smallest subarray with a given sum
• Other
  • Data structures
    • Linked List
    • Queue
    • Stack
    • Tree
      • Balanced binary tree
      • Binary tree traversals
    • Graph
    • Trie
    • Heap
    • Priority Queue
    • Bloom filter
    • LRU cache
  • Sorting
    • Bubble sort
    • Selection sort
    • Insertion sort
    • Merge Sort
    • Quicksort
    • Heapsort
    • Counting Sort
    • Radix Sort

Developing

Clean up, lint source files, run tests and be ready for a push:

make push-ready

Test only:

make test

Test and report:

make cover

Test verbose:

make test-verbose

Lint:

make lint

Clean up:

make clean

For more information:

make help

References

• Sorting algorithm cheat sheet
• LeetCode patterns
• LeetCode's 50 common interview questions
• Bitwise operators cheat sheet
• Practical Algorithms and Data Structures

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