Centre for Development of Advanced Computing Software Engineer Interview Questions and Answers

Hashtable is synchronized while hashmap is not.

• Hashtable is thread-safe while hashmap is not.

• Hashtable does not allow null keys or values while hashmap allows one null key and multiple null values.

• Hashtable is slower than hashmap due to synchronization.

• Hashtable is a legacy class while hashmap is a newer implementation.

Hashmap is not thread-safe while Concurrent Hashmap is thread-safe.

• Hashmap is not suitable for multi-threaded environments as it can lead to race conditions and data inconsistencies.

• Concurrent Hashmap allows multiple threads to access and modify the map concurrently without any data inconsistencies.

• Concurrent Hashmap uses a technique called lock striping to achieve thread-safety.

• Concurrent Hashmap is slower than Hashma...read more

I am proficient in Java, Python, and C++. I have 2 years of experience in software development. I have excellent communication skills for client interaction.

• Proficient in Java, Python, and C++

• 2 years of software development experience

• Excellent communication skills for client interaction

To find the shortest path in a graph stored in SQL, use algorithms like Dijkstra's or A* with SQL queries for traversal.

• Use Dijkstra's algorithm for weighted graphs to find the shortest path efficiently.

• For unweighted graphs, consider using Breadth-First Search (BFS).

• Store graph edges in a table with columns for source, destination, and weight.

• Example SQL query: SELECT * FROM edges WHERE source = 'A' AND destination = ...read more