FaangDSA

Solutions to problems explained and taught in a video series.

Master coding interviews at FAANG - PSDS / DSA rounds problems / LeetCode problems

These videos are by ZerotoMastery.io

Problems:

Arrays

1. LeetCode Problem 1

   findTwoSum : Given an array of integers, return the indices of target sum.

2. LeetCode Problem 11

   Two Shifting Pointers - maxArea : Given an array of positive integers representing a vertical line on a chart, where the base is the x-axis, find two lines that would contain the greatest amount of water. return the area of water it would hold.

3. LeetCode Problem 42

   Hard array problem Critical thinking problem; Given an array of integers representing an elevation map, where width of each bar is 1, return how much rain water can be trapped

4. LeetCode Problem 844

   String problem - Backspace Compare - compare two strings A, B check if they are equal. every "#" is a backspace character.

5. LeetCode Problem 3

   String problem - Longest substring without repeating characters - Return the length of longest contigious substring without repeating characters

6. LeetCode Problem 125

   String Problem - Subproblem - Palindromes - Check if given string is a valid palindrome. Standard problem. Assume only alpha numberic characters are valid. remove spaces, punctuations, etc

7. Linked List Problem

   Reverse a given Linked List

8. Doubly linked list Problem

   Subproblem - Flatten a given doubly linked list

9. Cycle detection in a linked list

   Floyd's tortoise and hare algorithm - Implementation of the algo to check for cycle in a given linked list and get the starting point.

10. Stack Datastructure

    Subproblem - check for string with paranthesis for validity

11. Stack Problem

    Subproblem - Remove the least number of brackets to make a given string with brackets a valid string. It may only contain brackets and lower case characters.

12. Queue Datastructure

    Implement Queue using stack datastructure

13. Sorting Problem

    Get the Kth largest element of an unsorted array - Ignore duplicates - Use qick sort to sort the array first

    Get the Kth smallest element of an unsorted array - Hoare's quick select algorithm implementation

14. Binary Search Algorithm

    Input array is sorted in ascending order; find an element. Sub Problem - Find element's range in the sorted array. Use binary search to perform the secondary search in both directions.

15. Binary tree - Find max depth

    Given a tree, perform DFS and get depth of the tree.