DE Shaw campus interview questions 2026

• In a recent 2025 campus drive for DE Shaw, Bayes: disease test 98% sensitive, 1% prevalence — compute P(disease|+) under DE Shaw time pressure.
• A recurring screen item at DE Shaw: Walk through AR(1) process stability condition — quick time-series check at DE Shaw.
• One candidate reported that interviewers asked to Parse and evaluate arithmetic expression with + - * / and parentheses — stack discipline for DE Shaw.
• One candidate reported that interviewers asked to Dynamic programming: expected rolls to see all faces of a die — state graph for DE Shaw math screens.
• A common OA question at DE Shaw is to Grid shortest path with only right/down moves — Catalan-related count for DE Shaw pattern rounds.
• In a recent 2025 campus drive for DE Shaw, Write a function returning nth Fibonacci mod 1e9+7 with matrix exponentiation — speed target at DE Shaw.
• In a recent interview, Implement rolling hash for substring search with collision check — relevant to DE Shaw pattern modules.