# Coding problems using hashing

Hashing is a popular technique to solve many complex algorithmic problems in less time complexity. We often use HashMap using collections in java or map using STL in C++ but think in-depth about how hashing is used. That's why we have curated a dedicated section to showcase basic hashing to how hashing can be used to solve complex problems that can be featured in any interview rounds. Many of the problems which could have been solved using some other approaches have been solved efficiently using hashing here. Also, this section will help to brush up your knowledge on the low-level design on hashing so that you can design your hash table in your way:)

## List of coding problems using hashing

- Minimum deletions to make all elements same using hash table
- Maximum distance between two occurrences of same element in array
- Check if two arrays are similar or not using hashing
- Minimum number of operations to make all elements same using hashing
- First element occurring K times in the array using hashing
- Count maximum points on same line
- Sort elements by frequency
- Given an array A[] and number X, check for pair in A[] with sum X | using hashing O(n) time complexity | Set 1
- Given an array A[] and number X, check for pair in A[] with sum X | using two pointer algorithm, O(1) space complexity | Set 2
- Minimum Number of Steps to Make Two Strings Anagram

TOP Interview Coding Problems/Challenges

- Run-length encoding (find/print frequency of letters in a string)
- Sort an array of 0's, 1's and 2's in linear time complexity
- Checking Anagrams (check whether two string is anagrams or not)
- Relative sorting algorithm
- Finding subarray with given sum
- Find the level in a binary tree with given sum K
- Check whether a Binary Tree is BST (Binary Search Tree) or not
- 1[0]1 Pattern Count
- Capitalize first and last letter of each word in a line
- Print vertical sum of a binary tree
- Print Boundary Sum of a Binary Tree
- Reverse a single linked list
- Greedy Strategy to solve major algorithm problems
- Job sequencing problem
- Root to leaf Path Sum
- Exit Point in a Matrix
- Find length of loop in a linked list
- Toppers of Class
- Print All Nodes that don't have Sibling
- Transform to Sum Tree
- Shortest Source to Destination Path

Comments and Discussions