Citi Interview Questions
Master your tech interview with our curated database of real questions from top companies.
Implement bidirectional Dijkstra for shortest paths
Given a directed or undirected graph with non‑negative edge weights, design and implement bidirectional Dijkstra (“double Dijkstra”) to find the short...
Walk through resume and impact
Behavioral Interview: Resume Walkthrough and Project Deep Dive You are in an onsite Software Engineer interview. Provide a concise, outcome-focused wa...
Explain data structure fundamentals
Explain how a hash map works internally: hashing, collision resolution strategies (separate chaining vs. open addressing), load factor, and resizing. ...
Explain OS and networking basics
Systems Fundamentals Quickfire (Onsite Software Engineer) Answer concisely but precisely. Use diagrams or bullets if it helps. 1) Processes, Threads, ...
Solve two logic brain teasers
Two Classic Logic/Optimization Puzzles Puzzle 1: Heavier Ball with a Balance Scale You have 12 visually identical balls. Exactly one ball is heavier t...
Write SQL for 30-day activity and D7 retention
You are given two tables. Table: trades - user_id (BIGINT) - trade_time (TIMESTAMP) — timestamp of the trade - volume (NUMERIC) - asset (TEXT) Table: ...
Answer ownership and ambiguity behavioral questions
Behavioral interview prompts (Data Scientist, Risk / Product Analytics): 1. Tell me about a time data changed a decision. 2. When data quality was bad...
Design experiment and analyze volume drop scenario
Answer the following two prompts as a Data Scientist working on Risk / Product Analytics. --- Prompt 1 — Experiment design: increase new-user first tr...