Oracle Full Stack Developer Interview Questions and Answers

Inheritance is a concept in object-oriented programming where a class inherits properties and behaviors from another class.

• Inheritance allows for code reuse and promotes modularity.

• The class that is being inherited from is called the superclass or base class.

• The class that inherits from the superclass is called the subclass or derived class.

• The subclass can access the public and protected members of the superclass.

• Inhe...read more

Regular expressions in PHP are powerful tools for pattern matching and manipulating strings.

• Regular expressions are defined using the preg_match() function in PHP.

• They are used to search, replace, and validate strings based on specific patterns.

• Regex patterns consist of a combination of characters and special symbols.

• Modifiers can be added to the pattern to control the matching behavior.

• Common regex functions in PHP in...read more

Polymorphism is the ability of an object to take on many forms. It allows objects of different classes to be treated as the same type.

• Polymorphism allows a single interface to be used for different types of objects.

• It enables code reusability and flexibility in object-oriented programming.

• For example, a parent class 'Animal' can have multiple child classes like 'Dog', 'Cat', and 'Bird'. They can all be treated as 'Anim...read more

The code for finding the Lowest Common Ancestor (LCA) in a Binary Search Tree (BST).

• Start from the root node and compare it with the given two nodes.

• If both nodes are smaller than the current node, move to the left subtree.

• If both nodes are greater than the current node, move to the right subtree.

• If one node is smaller and the other is greater, then the current node is the LCA.

• Continue this process until the LCA is fou...read more

A DBMS for managing college faculty, professors, courses, and students.

• The DBMS should have tables for faculty, professors, courses, and students.

• Each table should have appropriate attributes to store relevant information.

• Relationships can be established between tables using foreign keys.

• Queries can be used to retrieve information about faculty, professors, courses, and students.

• The DBMS can be used to track enrollment...read more

I was actively involved in coding competitions, hackathons, and programming clubs during college.

• Participated in coding competitions such as ACM ICPC and Codeforces

• Attended hackathons to work on real-world projects and improve problem-solving skills

• Joined programming clubs to collaborate with peers and learn new technologies

Yes, I believe in seeking help when stuck in a problem as it leads to faster resolution and learning.

• I believe in collaborating with team members to brainstorm solutions

• I am not afraid to ask for help from more experienced developers

• I utilize online resources like Stack Overflow or documentation when needed

Teamwork is collaborating with others towards a common goal, utilizing each member's strengths and skills.

• Collaborating with others towards a common goal

• Utilizing each member's strengths and skills

• Communicating effectively and openly

• Respecting and valuing diverse perspectives

• Sharing responsibilities and supporting each other

• Celebrating successes as a team

When faced with an unsolvable problem, I break it down, research, seek help, experiment, and iterate until a solution is found.

• Break down the problem into smaller, manageable parts

• Research and gather information related to the problem

• Seek help from colleagues, online communities, or experts

• Experiment with different approaches or solutions

• Iterate and refine the solution based on feedback and results

In 5 years, I see myself as a senior software developer leading a team of developers on innovative projects.

• Leading a team of developers on innovative projects

• Senior software developer role

• Continuing to learn and grow in the field

Find the minimum and maximum values in an array in a single traversal.

• Initialize min and max variables with the first element of the array

• Iterate through the array and update min and max if a smaller or larger value is found

• Return the min and max values

The maximum number of squares on a chessboard is 64.

• The chessboard has 64 squares in total.

• The number of squares on a chessboard can be calculated using the formula n^2, where n is the number of rows or columns.

• In this case, n = 8 (8 rows and 8 columns), so the maximum number of squares is 8^2 = 64.

C++ is a programming language. Deep copy creates a new object and copies all values, while shallow copy creates a reference to the original object.

• C++ is a general-purpose programming language

• Deep copy creates a new object with its own copy of the data

• Shallow copy creates a reference to the original object

• Deep copy is safer but can be slower and consume more memory

• Shallow copy is faster but can lead to unexpected behav...read more

Pre initialization refers to the process of initializing variables or objects before they are used in a program.

• Pre initialization helps avoid errors or unexpected behavior caused by using uninitialized variables.

• It is a good practice to pre initialize variables with default values.

• Pre initialization can be done using constructors, default values, or initialization blocks.

• Example: int count = 0; initializes the variabl...read more

Reverse a linked list with and without using Recursion

• Iterative approach: Use three pointers to reverse the links between nodes

• Recursive approach: Recursively reverse the rest of the list and then fix the links

A copy constructor creates a new object as a copy of an existing object, ensuring proper resource management.

• Used to initialize an object using another object of the same class.

• Syntax: ClassName(const ClassName &obj) { /* copy data */ }

• Example: MyClass obj1; MyClass obj2 = obj1; // Calls copy constructor

• Important for classes that manage dynamic memory to avoid shallow copies.

• Default copy constructor performs a shal...read more

Polymorphism refers to the ability of an object to take on many forms. The diamond problem occurs in multiple inheritance.

• Polymorphism can be achieved through method overloading and method overriding.

• Method overloading allows multiple methods with the same name but different parameters.

• Method overriding occurs when a subclass provides a specific implementation of a method already defined in its superclass.

• The diamond p...read more

The program should differentiate between integers and characters when using the assignment operator (=).

• Check the data type of the variable before assigning a value.

• Use conditional statements to perform different actions based on the data type.

• For integers, assign the value directly. For characters, convert the character to its ASCII value and assign it.

Sort an array by moving all zeroes to the end.

• Iterate through the array and move all non-zero elements to the front.

• Count the number of zeroes encountered and append them at the end of the array.

• Use two pointers to swap elements and maintain the order.

The number of VTables created in a class hierarchy depends on the number of virtual functions and the number of derived classes.

• VTables are used in object-oriented programming languages to implement dynamic dispatch.

• Each class with at least one virtual function has its own VTable.

• Derived classes inherit the VTable of their base class and add their own entries for any additional virtual functions.

• The total number of VTa...read more

List is preferred when frequent insertion and deletion is required. Vector is preferred when random access is required.

• List is implemented as a doubly-linked list, allowing for efficient insertion and deletion at any position.

• Vector is implemented as a dynamic array, allowing for efficient random access.

• Use List when the number of elements is expected to change frequently and the order of elements matters less.

• Use Vect...read more

The given string needs to be reversed and the words need to be rearranged.

• Split the string into an array of words

• Reverse the array

• Join the array elements with a space in between