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Leetcode 71 - Simplify Path
Today let's work on processing unix paths with Leetcode 92 Simplify Path.
- leetcode
- linked list
- typescript
Latest Leetcode Solutions
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Leetcode 92 - Reverse Linked List II
Today let's have some fun reversing linked lists with Leetcode 92 Reverse Linked List II.
- leetcode
- linked list
- typescript
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Leetcode 83. Remove Duplicates From Sorted List
Today we will be going over Leetcode 83 Remove Duplicates From Sorted List. This will be a pretty straightforward linked list problem with a small catch.
- leetcode
- algorithms
- typescript
- linked list
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Leetcode 876 - Middle of the Linked List
After a long stint in hash table land it's time to move onto another class of data structures and algorithms. We are going to start out with linked lists by solving a classic problem in Leetcode 876 Middle of the Linked List.
- leetcode
- algorithms
- typescript
- linked list
- two pointers
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Leetcode 3 - Longest Substring Without Repeating Characters
Today we will be going over Leetcode 3 Longest Substring Without Repeating Characters. This problem combines two techniques (no spoilers, let's talk about it in the analysis section!)
- leetcode
- algorithms
- typescript
- hash table
- two pointer
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Leetcode 771. Jewels and Stones
Let's look at an easy hash table problem in LeetCode 771 Jewels and Stones
- leetcode
- array
- hashtable
- easy
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Leetcode 383 - Ransom Note
Today we will be going over Leetcode 383 Ransom Note. This is another example of using hash tables.
- leetcode
- algorithms
- typescript
- hash table
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Leetcode 525. Contiguous Array
With several hable table problems under our belt, lets do a slightly more difficult problem with Leetcode 525 Contiguous Array.
- leetcode
- algorithms
- typescript
- hash table
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Leetcode 1133 - Largest Unique Number
Today we will be using hash tables to find the largest unique number in an array in Leetcode 1133 Largest Unique Number.
- leetcode
- hash table
- typescript
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Leetcode 1189 - Maximum Number of Balloons
Let's work on a slightly more advanced hash table problem today with Leetcode 1189 Maximum Number of Balloons.
- leetcode
- hash table
- typescript
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Leetcode 2225. Find Players With Zero or One Losses
Today we will be going over Leetcode 2225 Find Players With Zero or One Losses. This is a hash table problem that requires us to keep track of the number of wins and losses for each player.
- leetcode
- algorithms
- typescript
- hash table
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Leetcode 1426. Counting Elements
Today we will be going over Leetcode 1426 Counting Elements. This is a fairly classic hash table problem.
- leetcode
- algorithms
- typescript
- hash table
- Published on
Leetcode 268 - Missing Number
Let's continue our trend of working hash table problems by solving Leetcode 268 Missing Number.
- leetcode
- algorithms
- typescript
- hash table
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Leetcode 1832. Check if the Sentence Is Pangram
After several days of reviewing prefix sum and sliding windows problem, I feel it's a great time for a change of pace. Today (and over the course of the next few days) we will start to discuss using hash tables. Hash tables are a common data structure used in algorithms and competitive programming to solve countinglike problems. The advantage is that by iterating once through our input we create a dictionary that can be used to iterate through later on in a problem. We should get plenty of practice on this the next several blogposts!
- leetcode
- algorithms
- typescript
- hash table
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Leetcode 2090. K Radius Subarray Averages
Today we will be going over Leetcode 2090 K Radius Subarray Averages. This is a slightly more advanced problem that requires the usage of the prefix sum technique.
- leetcode
- algorithms
- typescript
- prefix sum
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Leetcode 1413. Minimum Value to Get Positive Step by Step Sum
Today we will be going over Leetcode 1413 Minimum Value to Get Positive Step by Step Sum. In a previous blogpost we discussed the concept of prefix sums. Today we are going to have a chance to implement this concept in a real problem!
- leetcode
- algorithms
- typescript
- prefix sum
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Leetcode 1480. Running Sum of 1d Array
Today we will be going over Leetcode 1480 Running Sum of 1d Array. Our problem is a bit unique in that it really is just an introduction to the concept of using prefix sums. As such, this will be a relatively short post. But it will serve as the basis for a lot of problems we will see in the future. Prefix sums are a very common concept in competitive programming and algorithms in general. The prefix sum technique is the idea to take a list of numbers, and transform it such that each number in the list it the cumulate sum of itself and all the previous numbers in the list. This is a unique property that can help us make certain problems that would normally take O(n^2) time take O(n) time. Thats a big difference!
- leetcode
- algorithms
- typescript
- prefix sum
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Leetcode 1004. Max Consecutive Ones III
Today we will be going over Leetcode 643 Maximum Consecutive Ones III. Yet again we will be leveraging the sliding window approach for this problem.
- leetcode
- algorithms
- typescript
- sliding window
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Leetcode 643. Maximum Average Subarray I
Today we will be going over Leetcode 643 Maximum Average Subarray I. This will be one of many sliding window problems we will be going over the next few weeks (and further on because, hey, there are a lot of them).
- leetcode
- algorithms
- typescript
- sliding window
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Leetcode 344 - Reverse String
Hello and welcome to another algorithm problem review! Today we will talk about a simple algorithm on how to reverse a string in Leetcode 206 Reverse Linked List
- leetcode
- two pointer
- string
- typescript
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Leetcode 977 - Squared of a Sorted Array
Hello! Let's continue our trend of working on twopointer algorithms. Today we will talk about how to return an array of sorted squares in Leetcode 977 Squares of a Sorted Array
- leetcode
- two pointer
- array
- typescript
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Leetcode 242 - Valid Anagram (JavaScript)
In my previous blogpost I discussed how palindromes are a great way to dip one's toes into algorithms. But an even simpler start is to work with an anagram. An anagram is a word that is formed from another using the original letters exactly once. So how would we go about determining whether one word is an anagram of another? Let's talk through how to solve Leetcode problem 242 Valid Anagram.
- leetcode
- anagram
- hashmap
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Leetcode 125 - Valid Palindrome (JavaScript)
Palindromes are among some the most common "entry level" algorithm problems. Specifically they are a great way to test for understanding of basic approaches to solving problems with strings and arrays. Let's talk through how to solve Leetcode problem 125 Valid Palindrome.
- leetcode
- palindrome
- two-pointer
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Leetcode 20. Valid Parentheses (JavaScript)
Today let's take a look at Leetcode problem 20 Valid Parentheses
- leetcode
- array
- stack
- easy
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Leetcode 103. Binary Tree Zigzag Level Order Traversal (JavaScript)
Today we will be reviewing Leetcode 103 Binary Tree Zigzag Level Order Traversal which provides a good use case for breadth first traversal (BFS) of a tree.
- leetcode
- bst
- bfs
- medium
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Leetcode 701. Insert into a binary search tree
Today we will be going over Leetcode 701 Insert into a binary search tree. This is a classic DFS (depthfirst search) problem we will implement using recursion.
- leetcode
- trees
- depth-first-search
- javascript
- binary-search-tree
- recursion
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Leetcode 111. Minimum Depth of Binary Tree
Today we will being going over Leetcode 111 Minimum Depth of Binary Tree. This is a classic DFS (depth first search) problem we will implement using recursion.
- leetcode
- trees
- depth-first-search
- javascript
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Leetcode 88. Merge Sorted Array (JavaScript)
Let's take a look at yet another classic inplace array problem with LeetCode 88 Merge Sorted Array
- leetcode
- array
- two-pointer
- easy
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Leetcode 27. Remove Element (JavaScript)
Let's take a look at a classic inplace array problem with LeetCode 27 Remove Element
- leetcode
- array
- two-pointer
- easy
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Leetcode 121. Best Time to Buy and Sell Stock (JavaScript)
It's time to mix an array problem with some light dynamic programming in LeetCode 121 Find Numbers with Even Number of Digits
- leetcode
- array
- dynamic-programming
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Leetcode 203 - Remove Linked List Elements
Hello there! Today we will continue our journey into linked lists with Leetcode 203 Remove Linked List Elements. This is a quite common question to solve with regards to efficiently removing nodes from a linked list.
- leetcode
- Published on
Leetcode 206 - Reverse Linked List
Hello and welcome to another algorithm problem review! Today we will continue diving down the linked list rabbit hole to discuss Leetcode 206 Reverse Linked List
- leetcode
- Published on
Leetcode 141 - Linked List Cycle
After a rash of string and array problems I thought we would take a break today and start discussing linked lists. To start out let's take a closer look at Leetcode 141 Linked List Cycle
- leetcode
- Published on
Leetcode 1295. Find Numbers with Even Number of Digits (JavaScript)
We continue looking into array problems with LeetCode 1295 Find Numbers with Even Number of Digits
- leetcode
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Leetcode 485. Max Consecutive Ones (JavaScript)
I am back after a brief hiatus! Over the next several posts we are going to cover some very common array problems. Let's start with LeetCode 485 Max Consecutive Ones
- leetcode
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Solving Leetcode 70 - Climbing Stairs (JavaScript) (Fibonacci sequence)
It's been a lot of fun completing one algorithm problem a day! I feel there is plenty time to go but I firmly believe given enough variety (and time) I will better master critical concepts. We previous have worked on two sum and atoi() which involve some clever tricks and helper methods that JavaScript provides. Today we are going to talk about something a little different and start dipping our toes into the concept of recursion and iterative solutions with leetcode 70 climbing stairs.
- leetcode
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Solving Leetcode 8 - String to Integer (atoi) (JavaScript)
atoi() is a very classic C library function that converts character string into an integer. Otherwise if it is unable to do so it returns the integer 0. Now of course if you've visited Mozilla's famous MDN website to get help on web technologies atoi conspiculously returns no results. Because as it turns out we have other methods/practices for converting numbers to string (and vice versa). But to me the real challenge of this problem is not necessarily figuring out how to convert a string to a number but rather all the corner cases one must consider to implement an atoi() function in JavaScript.
- leetcode
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Solving Leetcode 1 - Two Sum (JavaScript)
As I mentioned in my about me section I do not have a traditional CS degree. My background consists of being a former semiconductor test engineer with a MS in Electrical Engineering and a Bachelors in Applied Mathematics. I have learned so much in the past one and a half years as I have continued to build things.
- leetcode