Next Greater Element I
The next greater element of some element x in an array is the first greater element that is to the right of x in the same array...
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leetcode
python
monotonic stack
Leetcode Daily Temperatures
Given an array of integers temperatures represents the daily temperatures, return an array answer such that answer[i] is the number of days you have to wait after the ith day to get a warmer temperature. If there is no future day for which this is possible, keep answer[i] == 0 instead...
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leetcode
python
stack
java
Optimizing SQL Queries - Understanding and Refreshing Materialized Views
When to use a materialized view? And how does it perform against a normal view. Benchmarking using docker...
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sql
database
python
docker
Maximum Width of Binary Tree
The problem statement, as given on LeetCode, asks us to find the maximum width of a binary tree. The width of a level is defined as the number of nodes at that level. The maximum width of the binary tree is the maximum width among all levels...
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python
queue
java
Binary Tree Right Side View Leetcode
We delve into a popular algorithmic problem from LeetCode: the "Binary Tree Right Side View". This problem is an excellent exercise for understanding tree-based data structures and breadth-first traversal techniques...
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python
queue
java
Meetup at McColl School of Business at Queens University
I went to Charlotte Fintech Meetup. It was held in Room 326 of Sykes Hall, which is located in the McColl School of Business at Queens University. ...
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charlotte
finance
python
House Robber Leetcode Solution
You are a professional robber planning to rob houses along a street. Each house has a certain amount of money stashed, the only constraint stopping you from robbing each of them is that adjacent houses have security systems connected and it will automatically contact the police if two adjacent houses were broken into on the same night...
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javascript
java
python
rust
Publish to MSK Kafka using AWS Lambda Python
Apache Kafka is a distributed streaming platform designed to handle real-time data streams efficiently. It uses a publish-subscribe model, where producers publish messages to topics, and consumers subscribe to those topics to receive the messages. Amazon MSK simplifies the deployment and management of Kafka clusters on AWS, providing a fully managed and scalable solution. You can use AWS lambda in python to publish to MSK topic...
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kafka
aws
python
Fix SonarQube Error of Public Writable Directories in AWS lambda python
In AWS Lambda functions, it's common to use temporary directories for tasks like generating temporary files, storing intermediate data, or processing data securely. However, improperly managing publicly writable directories can lead to security vulnerabilities. In this article, we'll explore how to address this issue and ensure safe usage of temporary directories in AWS Lambda functions using Python's tempfile module...
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sonarqube
python
aws
Unit Test AWS Lambda Function in Python
AWS lambda function are event driven serverless code. To follow TDD, we should write unit test our lambda functions...
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aws
python
Pandas inner join on dataframes
Performing inner join on pandas dataframe is straightforward. However I wanted to override values from the right dataframe...
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python
pandas
Resolve the Error CROSSSLOT Keys in request don't hash to the same slot
AWS offers managed service Amazon MemoryDB which is redis compatible. The entire keyspace in Redis cluster is divided into hash slots and these slots are assigned to multiple nodes. In redis, getting a single value is straightforward...
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python
redis
memorydb
aws
Extract tweets from Twitter using Python
In this tutorial, we will extract tweets from Twitter using python...
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python
Serialize and Deserialize Binary Tree Leetcode solution
Design an algorithm to serialize and deserialize a binary tree. There is no restriction on how your serialization/deserialization algorithm should work. You just need to ensure that a binary tree can be serialized to a string and this string can be deserialized to the original tree structure...
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leetcode
java
python
design
Apply Discount To Prices leetcode solution
A sentence is a string of single-space separated words where each word can contain digits, lowercase letters, and the dollar sign '$'. A word represents a price if it is a sequence of digits preceded by a dollar sign...
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leetcode
java
python
string
Sort Characters By Frequency solution leetcode
Given a string s, sort it in decreasing order based on the frequency of the characters. The frequency of a character is the number of times it appears in the string...
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leetcode
java
python
heap
Create a Lambda Function to run SQL queries in Redshift Cluster
Amazon Redshift is fully managed warehouse service provided by AWS. The Amazon Redshift engine is a SQL-compliant, massively-parallel, query processing and database management system designed to support analytics workload...
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python
sql
lambda function
aws
redshift
Getting Started with decorators in Python
In python, everything is an object. So functons are also objects which can be passed around. A decorator is a function that receives a function and returns a function...
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python
Minimum Consecutive Cards to Pick up solution leetcode
An interesting problem on leetcode to find minimum number of ways to pick up consecutive cards. We will start with a brute force algorithm that would exceed in time limit. Later we will improve upon this algorithm using hashmap...
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leetcode
java
python
hashmap
Do you have triskaidekaphobia?
I grew up in India with a diet of basmati rice and superstition. I have seen pedestrians freezing at the sight of a black cat crossing their path for fear of bad luck. Lemon and chilis hang in front of vehicles to ward off bad spirits. I fondly remember numerous advertisements proclaiming protection from evil eyes. Recently I stumbled upon an ad that refreshed my memories...
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superstition
rationalism
python
Creating Python AWS lambda layer with Docker
When you develop AWS lambda functions, you might feel the need to install additional `python` libraries. This can be achieved using Lambda layers that can be included in any lambda function...
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docker
aws
python
Leetcode - All Divisions With the Highest Score of a Binary Array
You are given a **0-indexed** binary array `nums` of length `n`. `nums` can be divided at index `i` (where `0 <= i <= n`) into two arrays (possibly empty) nums
left and nums
right..
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leetcode
hashmap
array
java
python
Course Schedule Leetcode Solution
There are a total of numCourses courses you have to take, labeled from 0 to numCourses - 1. You are given an array prerequisites where prerequisites[i] = [a
i, b
i] indicates that you must take course b
i first if you want to take course a
i...
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leetcode
graph
bfs
java
python
Remove-all-adjacent-duplicates-in-string-ii Solution
You are given a string s and an integer k, a k duplicate removal consists of choosing k adjacent and equal letters from s and removing them, causing the left and the right side of the deleted substring to concatenate together...
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leetcode
stack
python
java
scala
javascript
Lowest Common Ancestor of a Binary Tree
Questions involving the binary tree data structure are very popular in tech interviews, and can be challenging and varied! A binary tree is a data structure consisting of a collection of nodes (starting at a root node), where each node consists of a value (data), together with a directed edges to at most two nodes (the "left child" and "right child"), with the additional conditions that no two edges point to the same node and no edge points to the root. I recently solved an interesting problem on binary tree...
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leetcode
java
python
javascript
scala
Ternary String solution Codeforces - 1354B
Ternary string is an interesting problem that could be solved using two pointers techniques. It's a convenient way to keep track of multiple indices. This helps in making decisions based on two values...
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codeforces
two pointers
java
python
Coin Change solution leetcode
It's one of the most popular questions on leetcode that seems very easy at first. Coin change is a classic dynamic programming problem. I will proceed with an obvious (albeit wrong) solution and subsequently proceed to an efficient correct solution...
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leetcode
dp
java
python
Maximum Subarray
There's an interesting problem I recently solved on leetcode based on dynamic programming. My
Github repository contains list of all problems that I have solved. I often start with a brute force approach without fretting about time complexity. Later I try to improve my algorithm for a better efficient solution...
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leetcode
dp
java
python
Getting Started with AWS CDK
Cloudformation service in AWS allows you to describe an entire set of resources required to make a pipeline. The cloudformation template can be described in JSON or YAML format. Updating the cloudformation template was not a pleasant experience. I wanted to discover alternative ways to generate cloudformation template programmatically...
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aws
cdk
cloudformation
typescript
python
How to Make(Or Lose) Money in Stocks Part1
Recently I finished watching web-series
Scam 1992. It's based on story of Harshad Mehta, a famous Indian stockbrocker who made fortunes in stocks. Despite his iconic success &
failure, the series rekindled my interest in world of "stocks". I guess the famous dialogue "Risk Hai Toh Ishq Hai" has stuck with me...
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stocks
python
finance
money
google
selenium
EnvCommandError in Windows using Poetry
Poetry is a great dependency management tool in python. It's better than managing a flat file like `requirements.txt`. There are also other great tools like pipenv. However I found poetry much simpler in resolving dependencies...
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windows
python
poetry
bug
Connect to an Oracle Database using kerberos with python
Jobs failed! Screamed an automatic failure alert in email inbox. Existing python scripts were failing in the server which fetched data from Oracle database. I wondered if the credentials had changed...
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kerberos
projects
python
docker
oracle
database
