COURSE BREAKDOWN

Java Interview Questions: Data Structures and Algorithms

Section 0: Introduction to Interview Questions

• Course Overview
• FizzBuzz: Print the numbers from 1 to 100 and for multiples of '3' print "Fizz" instead of the number and for the multiples of '5' print "Buzz".

Section 1: String/Array Interview Questions

• 01 Reverse Words in a String: Given an input string, reverse the string word by word.
  
• 02 Rotate Array: Rotate an array of n elements to the left by k steps.
  
• 03 Isomorphic Strings: Given two strings a and b, determine if they are isomorphic.
  
• 04 Kth Largest Element in an Array: Find the kth largest element in an unsorted array. Note that it is the kth largest element in the sorted order, not the kth distinct element.

Section 2: Matrix Interview Questions

• 01 Set Matrix Zeroes: Given a 2D matrix, if an element is 0, set its entire row and column to 0. Do it in place.
  
• 02 Spiral Matrix: Given a 2D matrix, return all elements of the matrix in spiral order.
  
• 03 Number of Islands: Given a 2D grid map of 1s (land) and 0s (water), count the number of islands.
  

Section 3: Linked List Interview Questions

• 01 Implement a Stack Using an Array in Java: Implement a stack using an array.
  
• 02 Add Two Numbers: You are given two linked lists representing two non-negative numbers. The digits are stored in reverse order and each of their nodes contain a single digit. Add the two numbers and return it as a linked list.
  
• 03 Reverse a Linked List: Reverse a singly linked list.
  

Section 4: Tree Interview Questions

• 01 Inorder Traversal: Perform inorder traversal on a binary tree.
  
• 02 Preorder Traversal: Perform inorder traversal on a binary tree.
  
• 03 Postorder Traversal: Perform inorder traversal on a binary tree.
  
• 04 Binary Tree Maximum Path Sum: Given a binary tree, find the maximum path sum.
  

Section 5: Graph Interview Questions

• 01 Clone an Undirected Graph: Each node in the graph contains a label and a list of its neighbors.

Section 6: Sorting and Time Complexity

• 01 Types of Time Complexity: Learn the types of time complexity in Big-O Notation in order of horrible to good.
  
• 02 Bubble Sort Algorithm: Sort a list with bubble sort.
  
• 03 Selection Sort Algorithm: Sort a list with selection sort.
  
• 04 Insertion Sort Algorithm: Sort a list with insertion sort.
  
• 05 Quick Sort Algorithm: Sort a list with Quick Sort.
  
• 06 Merge Sort Algorithm: Sort a list with Merge Sort.
  
• 07 Time Complexity of Different Sorting Algorithms
  

Section 7 Dynamic Programming Interview Questions

• 01 Coin Change: You are given coins of different denominations and a total amount of money amount. Write a function to compute the fewest number of coins that you need to make up that amount.
  
• 02 Edit Distance: Find the edit distance between two strings.
  
• 03 Distinct Subsequences: Given a string S and a string T, count the number of distinct subsequences of T in S.
  
• 04 Maximum Sum Subarray: Find the sum of contiguous subarray within a one-dimensional array of numbers which has the largest sum

Section 8 Bit Manipulation Interview Questions

• 01 Bitwise and Shift Operators: Manipulate bits and shift bits to change values.
  
• 02 Single Number: Given an array of integers, every element appears twice except for one. Find that single one.
  
• 03 Sum of Two Integers: Calculate the sum of two integers a and b, but you are not allowed to use the operator + and -.
  
• 04 Number of 1 Bits: Take an unsigned integer and return the number of ’1' bits it has (also known as the Hamming weight.)
  
• 05 Reverse Bits: Reverse the bits of a given 32 bit unsigned integer.
  
• 06 Bitwise AND of a Range: Given two non-negative long integers, a and b and given a <= b, find the bitwise AND of all integers from a and b.

Section 9 Combinations and Permutations Interview Questions

• 01 Permutations: Print all permutations of a given string.
  
• 02 Distinct Permutations of a String: Print all distinct permutations of a string that contains duplicates.
  
• 03 Letter Combinations of a Phone Number: Given a digit string, return all possible letter combinations that the number could represent on a phone board.
  
• 04 Factor Combination: Return all possible combinations of an integer n’s factors.

Section 10 Math Interview Questions

• 01 Reverse Integer: Reverse the digits of an integer n.
  
• 02 Palindrome Number: Determine whether an integer is a palindrome. Do this without extra space.
  
• 03 Excel Sheet Column Numbe: Given a column title from an Excel sheet, return its corresponding column number.