Advanced Java Problems

Advanced Java problems for QA Automation Tester interviews

The list starts simple and moves to more complex topics such as data structures and algorithms. These problems in increasing order of difficulty are as follows:

1. Check if a year is a leap year
2. Find the missing number in an array of 1 to N
3. Find the common elements between two arrays
4. Count the number of vowels and consonants in a string
5. Calculate the length of a string without using the length() method
6. Swap two numbers without using a temporary variable
7. Calculate the power of a number without using the Math class
8. Calculate the square root of a number without using the Math class
9. Calculate the area of a circle
10. Find the intersection of two arrays
11. Find the second largest element in an array
12. Calculate the average of an array of numbers
13. Implement a binary search algorithm
14. Implement a bubble sort algorithm
15. Implement a selection sort algorithm
16. Implement an insertion sort algorithm
17. Implement a quicksort algorithm
18. Implement a factorial function using recursion
19. Implement a Linked List
20. Find the reverse of this linked list
21. Remove duplicates from a sorted linked list
22. Check if two strings are anagrams
23. Convert a string to an integer
24. Convert an integer to a string
25. Calculate the GCD (Greatest Common Divisor) of two numbers
26. Check if a number is a perfect square
27. Implement a HashMap in Java
28. Implement a HashSet in Java