1582 articles
Recognising classical number sequences — Fibonacci, Catalan, triangular, Pascal-derived — is the difference between a 30-minute brute force and a 5-minute closed form. Master the recurrences, generating functions, and combinatorial interpretations every interviewer expects you to know.
Learn the Chinese Remainder Theorem from scratch. Understand the math, build CRT from extended GCD, handle non-coprime moduli, and ace cryptography and competitive programming interview questions.
Master square root decomposition for range sum, range minimum, and Mo's algorithm. The simplest range-query data structure that beats brute force for competitive programming and interviews.
Avoid silent overflow bugs and floating-point traps. Learn safe multiplication, modular arithmetic, BigInt, integer square root, and binary search on the answer for competitive programming and interviews.
Solve probability DP problems used by quantitative interviews. Master expected value recurrences, geometric distribution, knight probability, and the soup servings memoization trick.