A Math Academy review

A personal review of Math Academy from the perspective of a self-taught math-heavy user, focusing on its pedagogy, strengths, and annoyances.

Calibrating Confidence

A note on confidence calibration, why overconfidence and underconfidence both hurt decisions, and how to test and improve probabilistic judgement.

The intuition and the math behind Simpson's paradox

An intuition-first explanation of Simpson's paradox as a mismatch between local and global comparisons, followed by the algebra behind it.

Implementing FFT

A derivation-oriented guide to FFT implementations, moving from recursive Cooley-Tukey to iterative and in-place variants without explicit bit reversal.

On using RSS feeds

A short practical note on why RSS feeds are useful and how to start using them to follow blogs, research feeds, and other updates.

PSA: target pragmas won't work on the new g++-13 compiler on CF

A PSA about GCC 13 on Codeforces rejecting target pragmas, why the issue appears, and what changed in later GCC versions.

Convenient and near-optimal binary search on floating point numbers

A near-optimal floating-point binary search template that searches representable values via bit-casts instead of hard-coded iteration counts.

Write recursive DP without thinking about memoization

A C++ template for recursive DP with automatic memoization, built from recursive lambdas, generalized hashing, and policy-based hash tables.

An elementary way of solving recurrences

An elementary way to solve recurrences by changing variables until simpler structure appears, recovering characteristic-equation intuition without heavy machinery.

The Akra-Bazzi theorem - a generalization of the master theorem for recurrences

A practical introduction to the Akra-Bazzi theorem as a way to analyze divide-and-conquer recurrences with unequal splits, floors, and offsets.