Fashion Opticals Python Developer Interview Questions and Answers

Static class and static constructor in C#

• Static class can only contain static members and cannot be instantiated

• Static constructor is called only once when the class is first accessed

• Static constructor is used to initialize static members of the class

• Example: Math class in C# is a static class

• Example: static constructor can be used to initialize a static variable with a value

Performance improvement in Angular app

• Use lazy loading to load modules on demand

• Optimize change detection strategy

• Use trackBy function in ngFor loops

• Minimize DOM manipulation

• Use AOT compilation

• Implement server-side rendering

• Use web workers for heavy computations

• Use caching for frequently accessed data

Performing web application penetration testing on a website with firewall enabled.

• Identify the type of firewall and its configuration

• Perform reconnaissance to gather information about the target

• Identify vulnerabilities and exploit them

• Use tools like Burp Suite, Nmap, and Metasploit

• Test for common web application vulnerabilities like SQL injection and cross-site scripting

• Document findings and provide recommendations for

Steps for Azure migration from onprem to cloud and Hyper V migration using VMWARE tool.

• Assess on-premises environment

• Choose appropriate migration method

• Prepare Azure environment

• Migrate data and applications

• Optimize and secure migrated resources

• VMware tool used for migration: VMware vCenter Converter

• Hyper-V migration can be done using Azure Site Recovery

Memory management is crucial for efficient application performance.

• Memory allocation and deallocation should be done carefully to avoid memory leaks.

• Unused memory should be released to prevent memory fragmentation.

• Memory profiling tools can help identify memory-related issues.

• Caching can improve performance by reducing the need for frequent memory allocation.

• Examples: Java's garbage collector, C++'s smart pointers, iOS

Merge Sort is a divide and conquer algorithm that sorts an array by dividing it into two halves, sorting them separately, and then merging the sorted halves.

• Divide the array into two halves

• Recursively sort the two halves

• Merge the sorted halves

Find pairs of integers in a BST whose sum is equal to a given number.

• Traverse the BST and store the values in a hash set.

• For each node, check if (X - node.value) exists in the hash set.

• If yes, add the pair (node.value, X - node.value) to the result.

• Continue traversal until all nodes are processed.

Merge overlapping time intervals into mutually exclusive intervals.

• Sort the intervals based on their start time.

• Iterate through the intervals and merge overlapping intervals.

• Output the mutually exclusive intervals.

• Example: [(1,3), (2,6), (8,10), (15,18)] -> [(1,6), (8,10), (15,18)]

Different types of hashing and alternative for Linear Chaining

• Different types of hashing include division, multiplication, and universal hashing

• Alternative for Linear Chaining is Open Addressing

• Open Addressing includes Linear Probing, Quadratic Probing, and Double Hashing

An AVL tree is a self-balancing binary search tree where the heights of the left and right subtrees differ by at most one.

• AVL tree is a binary search tree with additional balance factor for each node.

• The balance factor is the difference between the heights of the left and right subtrees.

• Insertion and deletion operations in AVL tree maintain the balance factor to ensure the tree remains balanced.

• Rotations are performed ...read more

Find the minimum number of squares whose sum equals to a given number n.

• Use dynamic programming to solve the problem efficiently.

• Start with finding the square root of n and check if it is a perfect square.

• If not, then try to find the minimum number of squares required for the remaining number.

• Repeat the process until the remaining number becomes 0.

• Return the minimum number of squares required for the given number n.

Insertion sort for a singly linked list.

• Traverse the list and compare each node with the previous nodes

• If the current node is smaller, swap it with the previous node

• Repeat until the end of the list is reached

• Time complexity is O(n^2)