Practice
Mastering Your Coding Practice Test: Proven Strategies 2026
A coding practice test scores behavior, not style. How hidden acceptance tests actually work, and how to prepare for the checks that decide whether you pass.
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The Blog
Practical writing on learning to code the way the job actually works — languages, patterns, and how coding tests really judge your work.
JavaScript
JavaScript Iterate Over Array: Proven Patterns for 2026
for, for...of, forEach, map, filter, reduce and custom iterators — which array iteration pattern fits the job, and where each one starts fighting you.
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Python
Complex in Python: A Practical Guide to Complex Numbers
What the j suffix means, when to reach for the built-in complex type, cmath or NumPy, and the branch-cut edge cases that quietly break numeric code.
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