Barclays Investment Bank Senior Software Developer Interview Questions and Answers

Multi tasking, multi processing, and multi programming are different approaches to managing tasks in an operating system.

• Multi tasking allows multiple tasks to run concurrently on a single processor.

• Multi processing involves multiple processors running tasks simultaneously.

• Multi programming allows multiple programs to be loaded into memory and executed concurrently.

• Examples of multi tasking operating systems include Wi...read more

Memory allocation refers to the process of assigning memory to programs during runtime.

• Stack allocation is done automatically and is limited in size.

• Heap allocation is done manually and is larger in size.

• Stack memory is used for local variables and function calls.

• Heap memory is used for dynamic memory allocation.

• Memory leaks can occur if heap memory is not properly managed.

Use a shared variable and synchronization mechanisms to ensure natural order printing of numbers.

• Create two threads, one for printing even numbers and the other for printing odd numbers.

• Use a shared variable to keep track of the current number to be printed.

• Implement synchronization mechanisms like locks or semaphores to ensure only one thread can access the shared variable at a time.

• Each thread should check if it is i...read more

Printing a matrix in spiral order

• Start from the first element and print it

• Move in a spiral order towards the center of the matrix

• Repeat until all elements are printed

Thread class and Runnable Interface are used for multithreading in Java.

• Thread class is a predefined class in Java that provides methods to create and control threads.

• Runnable interface is used to define a task that can be executed by a thread.

• Thread class implements Runnable interface.

• Thread class provides more control over threads than Runnable interface.

• Example: Thread t = new Thread(new MyRunnable()); t.start();

• Exa...read more

Linked List is a dynamic data structure while ArrayList is a static data structure.

• Linked List is best for frequent insertion and deletion operations.

• ArrayList is best for frequent access operations.

• Linked List uses more memory than ArrayList.

• ArrayList is faster than Linked List for accessing elements.

• Use Linked List when you need to frequently add or remove elements from the list.

• Use ArrayList when you need to frequen

I am not interested in a career in investment banking.

• I am more interested in a career in software development

• I enjoy problem-solving and creating innovative solutions through coding

• Investment banking does not align with my passion and skill set

I have chosen to apply to J.P. Morgan because of their reputation, global presence, and opportunities for growth.

• J.P. Morgan has a strong reputation in the financial industry.

• They have a global presence with offices in multiple countries.

• The company offers various opportunities for career growth and development.

• J.P. Morgan is known for its innovative technology solutions in the financial sector.

• I am impressed by their ...read more

Yes, I have made a mistake in my previous project.

• I underestimated the complexity of a task and ended up missing the deadline.

• I failed to properly test a feature, resulting in a bug that affected user experience.

• I accidentally deleted an important file without having a backup.

• I misunderstood a requirement and implemented a feature incorrectly.

Code for rand7 using rand5 function

• Use rand5 twice to generate a number in [1,25] with equal probability

• If the number is greater than 21, discard and try again

• Otherwise, return (number mod 7) + 1

LRU cache is implemented using a doubly linked list and a hash map.

• Create a doubly linked list to keep track of the order of elements in the cache.

• Create a hash map to store the key-value pairs of the cache.

• When a new element is added, check if the cache is full. If it is, remove the least recently used element from the linked list and the hash map.

• When an element is accessed, move it to the front of the linked list to...read more

Function to randomly select pivot element in Quick Sort

• Generate a random index within the range of the array

• Return the element at the randomly generated index as the pivot

Implement LRU cache

• LRU stands for Least Recently Used

• It is a cache eviction policy that removes the least recently used item

• It can be implemented using a doubly linked list and a hash map

• Newly accessed items are moved to the front of the list

• When the cache is full, the item at the end of the list is removed

Virtual memory is a memory management technique that allows a computer to use more memory than it physically has.

• Virtual memory uses a combination of RAM and hard disk space to store data.

• It allows programs to use more memory than is physically available.

• If a program tries to access memory that is not currently in RAM, it will be swapped in from the hard disk.

• Even if we had infinite RAM, virtual memory would still be n...read more

Find maximum length of subarray where max <= 2*min.

• Iterate through array and keep track of max and min values.

• Update max length when condition is met.

• Time complexity: O(n)