Varian Medical Systems Senior Software Engineer Interview Questions and Answers

To find code performance issues in production, use monitoring tools and profiling techniques.

• Use monitoring tools like New Relic, AppDynamics, or Datadog to track performance metrics and identify bottlenecks.

• Use profiling techniques like CPU profiling, memory profiling, and network profiling to pinpoint specific areas of the code that are causing performance issues.

• Analyze logs and error messages to identify patterns a...read more

Asynchronous programming is a programming paradigm that allows multiple tasks to run concurrently without blocking each other.

• Asynchronous programming is used to improve the performance of applications that require a lot of I/O operations.

• It involves the use of callbacks, promises, and async/await keywords in JavaScript.

• Asynchronous programming can be used in both front-end and back-end development.

• Examples of asynchro...read more

Program to change background color on button click in Angular

• Create a button in Angular template

• Add click event listener to the button

• Use setInterval() function to change background color after every 0.5 sec

• Use ngStyle directive to change background color dynamically

Use Angular's 'resolve' property to load component after services are loaded.

• Create a resolver service that waits for all three services to complete before resolving.

• Add the resolver service to the 'resolve' property of the component's route.

• Access the resolved data in the component using the ActivatedRoute service.

• Example: { path: 'my-component', component: MyComponent, resolve: { data: MyResolverService } }

IQueryable is for querying data from a source that implements IQueryable interface while IEnumerable is for iterating over a collection of data.

• IQueryable is used for deferred execution while IEnumerable is used for immediate execution.

• IQueryable is used for querying data from a remote data source while IEnumerable is used for querying data from an in-memory collection.

• IQueryable is more efficient for large datasets as...read more

Entity Framework is an ORM while ADO.NET is a data access technology.

• Entity Framework is easier to use and provides more abstraction than ADO.NET.

• ADO.NET is faster and more flexible than Entity Framework.

• Use Entity Framework for simple CRUD operations and ADO.NET for complex queries and performance-critical applications.

Spring Boot is a framework for building standalone, production-grade Spring-based applications.

• Spring Boot provides a simpler and faster way to set up, configure, and run both web and non-web applications.

• Annotations used in Spring Boot include @SpringBootApplication, @RestController, @RequestMapping, @Autowired, and @ComponentScan.

• These annotations help with configuration, dependency injection, and mapping HTTP reques

Find the smallest positive integer missing from an array of integers

• Iterate through the array and mark the presence of each positive integer

• Then find the smallest positive integer that is not marked

Generate a stream of numbers and explain how to efficiently process them.

• Use a generator function to produce an infinite stream of numbers.

• Implement a buffer to store a limited number of generated numbers at a time.

• Use a loop to process the numbers in the buffer efficiently.