Java

SQL queries: finding couriers with undelivered orders

How to convert a regular class into an immutable object

Junior — Middle+

IT One

Creating missing tables before inserting records with foreign keys

Employees with a missing manager in the database

Junior — Senior

МТС

Top 10 numbers receiving the most SMS

Junior — Senior

СБЕР

Connection pool calibration for stable load

Junior — Senior

Альфа-Банк

Designing a video upload module for a hypothetical video hosting service

Check if two strings are anagrams

Converting Stream to Set and List: Differences and Nuances

Revision and improvement of the money transfer function in Kotlin

Junior — Middle+

Самокат

Finding the longest common prefix in an array of strings

In‑memory financial ledger service implementation

Database schema optimization

Find the two largest elements of the array

Detection of a defect in the function of merging two lists

Junior — Senior

СБЕР

Removing duplicate person records by last name using Stream API

Searching for a target element in a sorted array

Refactoring the report generation method

Safe access to list element by index

Service: reliable creation and extraction of records

Junior — Senior

МТС