Oracle | Software Engineer | Onsite | Bengaluru | [offer]

Round 1: On-site Interview (Technical Round)

Questions:

• Java and OOP Questions:

  • Why does Java have wrapper classes for primitive data types?
  • Analyze and explain the output of the following code:

    public class Main(){
        public static void main(String[] arg){
            String name = "Name";
            String name1 = new String("Name");
            system.out.print(name == name1);
            return;
        }
    };

  • Further questions on OOP covered inheritance, different types of inheritance, and whether Java supports multiple inheritance.
  • Questions on abstract classes and several code analysis tasks were presented, including the following code samples:

    public class Main(){
        int a = 20;
        public static void main(String[] arg){
            system.out.print(a);
            return;
        }
    };

    class A{
        public void fun(){
            System.out.print("Hello from A");
        }
    };
    
    class B extends A{
        public void fun(){
            System.out.print("Hello from B");
        }
        public void fun1(){
            System.out.print("Hello from function1");
            return;
        }
    };
    
    public class Main(){
        public static void main(String[] arg){
            // In the discussion they have added each line of code and ask output.
            A obj = new A();
            B obj1 = new B();
            obj.fun();
            obj1.fun();
            obj1.fun1();
            obj = new B();
            obj.fun();
            obj.fun1();
            obj1 = new A();
            obj1.fun();
            obj1.fun1();
            return;
        }
    }

    abstract class A{
        public abstract void fun();
        public static void fun1(){
            System.out.print("Hello world!");
        }
    };
    
    public class Main(){
        public static void main(String[] arg){
            A.fun1();
            return;
        }
    };

• DSA Questions:

  1. Maximum Sum Subarray: The interviewer noted my familiarity with the problem and asked me to explain the approach to confirm my understanding.
  2. Median of an Array of Integers: Initially, I proposed sorting the array, but when they added that the integers were received as a stream, I suggested an insertion sort and then refined it using two priority queues.

• SQL Questions: Based on my project experience (YouTube clone), the interviewers presented a scenario involving user, video, and comment tables. They asked me to write a query to retrieve the name of the user whose video had the maximum number of comments.

• Puzzles:

  1. 3 Bulbs and 3 Switches from gfg.
  2. 8 balls problem from gfg.
  3. 10 Coins Puzzle from gfg.
  4. The final puzzle involved a scenario with five houses and a thief who changes houses daily, moving to an adjacent house. I was asked to devise the optimal strategy for the police to catch the thief and calculate the minimum number of days required.

Round 2: On-site Interview (Technical Round)

Questions:

• Quantitative Questions:

  1. A time and work-related problem.
  2. A permutation and combination (PNC) problem.

• System Design (High-Level Design): I was asked to design an elevator system for a 10-floor building with four elevator cars.

Final Stages

Three days after the interviews, I received a call from a manager who conducted a deep-dive review of my CV. At the end of the call, the manager verbally confirmed the offer.

One week later, I received an email regarding the background verification process, and after approximately 2 months, I received the official offer letter.