Algorithms

⏱ 7 min read Knapsack problems are the most important dynamic programming pattern class. Mastering 0/1 knapsack, unbounded knapsack, and their variants (subset sum, […] Read article

⏱ 7 min read Sliding window and two pointer techniques are among the most frequently tested patterns in coding interviews. They convert O(n²) or Read article

⏱ 8 min read Tries (prefix trees) and string algorithms appear in autocomplete, spell checking, IP routing, and competitive programming. Mastering trie construction and Read article

⏱ 7 min read When to Use a Heap A heap (priority queue) is the right data structure when you need: the minimum or Read article

⏱ 12 min read Beyond Basic DP Once you’ve mastered 1D/2D tabulation and memoization (Fibonacci, LCS, Knapsack, Coin Change), advanced interview problems require recognizing Read article

⏱ 10 min read Scala Interview Overview Scala is the language of Apache Spark, Kafka (originally), Akka, and many financial systems. Interviews at data Read article

⏱ 4 min read Why Hash Tables? Hash tables provide O(1) average-case lookup, insertion, and deletion — making them the most versatile data structure Read article

⏱ 4 min read PHP Interview Questions Overview PHP powers 77% of websites with a server-side language (including WordPress, Facebook’s HHVM era, Shopify’s partner Read article

⏱ 4 min read String and Array Patterns Overview String and array manipulation problems are a staple of coding interviews at every level. The Read article

⏱ 5 min read Rails Interview Questions Overview Ruby on Rails powers Shopify, GitHub (partially), Airbnb, and many startups. Senior Rails interviews test deep Read article

⏱ 6 min read Why Greedy and Interval Problems Greedy algorithms appear frequently in FAANG interviews because they test whether you can identify when Read article

⏱ 5 min read When to Use Range Query Data Structures Range query problems appear frequently in senior engineering interviews and competitive programming: “find Read article

⏱ 9 min read Swift Interview Questions Overview iOS engineering roles at Apple, Airbnb, Uber, and fintech companies require deep Swift knowledge. Interviewers test Read article

⏱ 9 min read Senior Java interviews at Google, Amazon, LinkedIn, and enterprise shops go deep on JVM internals, concurrency, and the language semantics Read article

⏱ 8 min read Bit manipulation problems appear at Google, Meta, and Amazon interviews. They test low-level reasoning and often offer O(1) space solutions Read article