On lambdas, C++ and otherwise: the what, the why, and the how

A tutorial on lambdas, from lambda-calculus context and C++ closure mechanics to recursion, stateful patterns, STL use, and competitive-programming examples.

A practical theoretically faster variant of the Euclidean GCD algorithm

A note on a Euclidean GCD variant that greedily reduces the remainder, with benchmarks and an iteration-count improvement.

Avoiding temporaries - generalizing i++ using std::exchange

A discussion and generalization of post-increment through std::exchange, with examples in recurrences, GCD code, lazy updates, moves, locks, and iterators.

The Boost C++ library in competitive programming

The Boost C++ library and examples of what it would give competitive programmers beyond the standard library.

PSA: Increase your stack size before the Meta Hacker Cup, here's how

A short PSA on increasing stack limits before MHC, with commands, compiler flags, and platform caveats.

The Floyd-Warshall algorithm and its generalizations

A tour of Floyd-Warshall as an instance of aggregating over graph paths, leading to transitive closure, Kleene algebras, and the algebraic path problem.

User editorial for Codeforces Round 513 by Barcelona Bootcamp (rated, Div. 1 + Div. 2)

A user-written editorial for Codeforces Round 513, which did not have an editorial before.

Floors, ceilings and inequalities for beginners (with some programming tips)

A beginner guide to inequalities involving floors and ceilings, with algebraic rules, examples, identities, and programming-language caveats.

Preserving Hash Code?

On preserving Google Hash Code problems and infrastructure before the contest archive disappears.

How to learn better, and what most people don't get about learning

A personal model of learning as building and querying a knowledge graph, with advice on theory, problem solving, creativity, feedback, and overfitting.