Collections and Data Shaping

Calculate invoice total with discounts

Implements invoice total calculation with quantity, unit price, percentage discount, and rounding.

Choose between an array, List<T>, and LinkedList<T> in C#

Chooses a sequential collection from size, mutation, access pattern, memory locality, and the behavior callers actually need.

Choose between Join, ToLookup, and repeated scans

Avoids hidden quadratic work by indexing repeated matches while preserving duplicate, missing, ordering, and memory semantics.

Choose string comparers for keys, membership, and sorting

Separates ordinal identity comparison from culture-aware display ordering and keeps hash-based collection semantics consistent.

Chunk items for batch processing

Implements chunking for batch processing without dropping final partial batches.

Collection operation complexity and real runtime costs

Uses complexity as a first filter while accounting for constants, locality, allocations, data size, and the complete operation sequence.

C# Practical Coding Problems

Hands-on coding rounds with practical C# data, API, and reliability exercises.

A practical C# coding interview track covering strings, dictionaries, grouping, parsing, pagination, validation, rate limiting, retry, caches, log aggregation, and edge-case thinking.