Kenji Watanabe
Technical Editor, Algorithms
Kenji writes the algorithms and data structures coverage: coding patterns, LeetCode strategy, complexity analysis, and language-specific interview questions with working code.
- Algorithms
- Coding patterns
- LeetCode strategy
Articles by Kenji Watanabe
Python Interview Questions for Software Engineers (2026)
The Python interview questions that actually come up in 2026, sorted by level, with the exact outputs interviewers expect and guidance on how deep each answer should go.
Design Patterns Interview Questions: OOP and SOLID (2026)
Interviewers rarely ask you to recite the Gang of Four catalog. They hand you messy code and watch which pattern you reach for. This guide maps the 10 most-asked patterns to the problems they solve, with before/after refactors.
SQL Window Functions Interview Questions with Examples (2026)
Window functions show up constantly in data and backend SQL rounds. Here are ten classic problems, each solved with the query and a step-by-step result table.
Bit Manipulation Interview Questions: 15 Tricks and Patterns
Most bit manipulation interview questions reuse the same fifteen operations. This guide shows each trick in binary, explains why it works, and maps it to the problems it solves.
How to Think Out Loud in a Coding Interview (With Scripts)
Interviewers can only score the reasoning they hear. This guide gives you exact phrases for every phase of a coding interview and shows a silent and a narrated solve side by side.
Graph Algorithms for Coding Interviews: The 2026 Guide
Six graph algorithms cover almost every graph question in a coding interview. This guide shows you how to recognize which one a problem needs and gives you a tested Python template for each.
Coding Interview Patterns Cheat Sheet (2026 Templates)
Most coding interview problems are variations of about fifteen patterns. This cheat sheet gives you the recognition signals, a Python template, complexity, and practice problems for each.
Java Interview Questions for Software Engineers (2026 Guide)
The Java interview questions backend engineers actually get in 2026, organized by topic with model answers. Includes the Java 21 and Java 25 features that older question lists still miss.
Golang Interview Questions for Backend Engineers (2026 Guide)
Go interviews filter candidates on concurrency, not syntax. This guide covers the Golang interview questions that actually come up in 2026, with worked worker pool, fan-in, context, and race detection examples.