Top 40 Java Interview Coding Questions

In this post, we have listed some of the most common java interview coding questions. Hope you find these useful.

List of java interview coding questions:

  1. Write a program to reverse a string using recursive algorithm.
  2. Write a program to reverse a number.
  3. Find longest substring without repeating characters.
  4. Write a program to find sum of each digit in the given number using recursion.
  5. Write a program to check the given number is a prime number or not?
  6. Write a program to remove duplicates from sorted array.
  7. Write a program to check the given number is binary number or not?
  8. How to check the given Binary Tree is Binary Search Tree (BST) or not?
  9. Find min and max value from Binary Search Tree (BST)
  10. Find out duplicate number between 1 to N numbers.
  11. Write a program to find maximum repeated words from a file.
  12. Implement Binary Search Tree (BST) post-order traversal (depth first).
  13. Write a program for Bubble Sort in java.
  14. Write a program to convert binary to decimal number.
  15. Write a program to find out duplicate characters in a string.
  16. Write a program to convert string to number without using Integer.parseInt() method.
  17. Write a program to sort a map by value.
  18. Write a program to find the given number is Armstrong number or not?
  19. Implement Binary Search Tree (BST) pre-order traversal (depth first).
  20. Write a program to get distinct word list from the given file.
  21. Write a program to print fibonacci series.
  22. Write a program to implement ArrayList.
  23. Write a program to convert decimal number to binary format.
  24. Write a program to find top two maximum numbers in a array.
  25. Find height of a Binary Search Tree (BST)
  26. Write a program for Insertion Sort in java.
  27. How to delete a node from Binary Search Tree (BST)?
  28. How to reverse Singly Linked List?
  29. Implement Binary Search Tree (BST)
  30. Write a program to find the sum of the first 1000 prime numbers.
  31. How to sort a Stack using a temporary Stack?
  32. Write a program to find two lines with max characters in descending order.
  33. How to get distinct elements from an array by avoiding duplicate elements?
  34. Write a program to implement hashcode and equals.
  35. Write a program to create deadlock between two threads.
  36. Find out middle index where sum of both ends are equal.
  37. Write a program to print all permutations of a given string.
  38. Write a program to get a line with max word count from the given file.
  39. Implement Binary Search Tree (BST) Level order traversal (breadth first).
  40. Implement Binary Search Tree (BST) in-order traversal (depth first).

Leave a Reply

Your email address will not be published. Required fields are marked *