- OOPs concepts ( mostly polymorphism and difference between encapsulation and abstraction)
- Difference between abstract class and interface.
- Difference between == and .equals() functions.
- What is Hash Map ?
- What is Hash Table ?
- Types of Exceptions.
- Difference between Exceptions and Errors.
- Difference between throw, throws and throwable.
- Difference between final, finalize and finally.
- What is class?
- What is an object?
- Difference between class and object.
- Method overloading.
- Method overriding.
- What is a thread?
- Different ways to create threads.
- Difference between C and Java.
- Difference between CPP and Java.
- File handling in java.
- Binary Search
- Quick Sort (Complexity and logic )
- Merge Sort (Complexity and logic )
- Difference between Merge sort, Quick sort
- Which one is better Merge sort or Quick sort and why ?
- What is a binary tree?
- What is binary search tree?
- What is linked list and its types.
- Implement stack/queue using linked list.
- Memory management (Heap and stack )
- AVL tree
- Difference between array and linked list.
- Reverse a linked list.
- Find middle element of a linked list.
- How to Detect loop in a linked list?
- Top view / Left view / Right view / Diagonal view of binary tree
- Right rotate a matrix
- Check if a binary tree is sub tree of another binary tree.
- Difference between process and thread.
- What is dead lock?
- Critical Section Problem
- What is Thrashing ?
- Page Fault.
- Difference between Primary key and Candidate key.
- What are Joins and types of Joins.
- Find second highest salary from Employee table.
- ACID Properties.
- Reverse a string.
- Find maximum occurring character/word in a given string.
- Recursively check if a given string is a palindrome.
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