--- title: "#30-days-of-code articles | Hashnode" description: "Explore 136 articles tagged #30-days-of-code on Hashnode. Tutorials, guides, and how-tos from the community." url: "https://hashnode.com/tag/30-days-of-code" --- Tag # #30-days-of-code 136 posts · 3 followers [Mustapha Muhammad Ibrahim](https://hashnode.com/@AL-Mustapha) · [Jul 6](https://hashnode.com/posts/day-03-06/6a4bb5f013234042bc02612d) ### [Day 03 - 06](https://mlbro.hashnode.dev/day-03-06?utm_source=hashnode&utm_medium=feed) A lazy techy doing a 30 days of ML , if you thinks its late start now. 5 min read · [mlbro.hashnode.dev](https://mlbro.hashnode.dev/day-03-06?utm_source=hashnode&utm_medium=feed) [Mustapha Muhammad Ibrahim](https://hashnode.com/@AL-Mustapha) · [Jul 2](https://hashnode.com/posts/30-days-of-machine-learning-ai/6a468d5908af912ab65a73a3) ### [Day-02](https://mlbro.hashnode.dev/30-days-of-machine-learning-ai?utm_source=hashnode&utm_medium=feed) 30 Days of Machine Learning & AI 6 min read · [mlbro.hashnode.dev](https://mlbro.hashnode.dev/30-days-of-machine-learning-ai?utm_source=hashnode&utm_medium=feed) [Tanishi](https://hashnode.com/@tanishi) · [Jan 8](https://hashnode.com/posts/day-9-intersection-of-two-linked-lists-two-pointer-leetcode-challenge/696159e68107f8a46e07da33) ### [Day 9 – Intersection of Two Linked Lists | Two Pointer | LeetCode Challenge](https://codingchallenge.hashnode.dev/day-9-intersection-of-two-linked-lists-two-pointer-leetcode-challenge?utm_source=hashnode&utm_medium=feed) 🗓️ Date: January 9, 2026📌 Challenge:🧩 Problem: Intersection of Two Linked Lists – LeetCode #160 (Easy)💻 Topic: Two Pointer, Linked List ✅ Problem Statement (Summary): Goal: Given the heads of two singly linked lists headA and headB, return the n... 2 min read · [codingchallenge.hashnode.dev](https://codingchallenge.hashnode.dev/day-9-intersection-of-two-linked-lists-two-pointer-leetcode-challenge?utm_source=hashnode&utm_medium=feed) [Tanishi](https://hashnode.com/@tanishi) · [Jan 7](https://hashnode.com/posts/day-8-linked-list-cycle-and-middle-of-the-linked-list-slow-and-fast-pointer-leetcode-challenge/69600cb7d87fdb9d8dade2ed) ### [Day 8 – Linked List Cycle & Middle of the Linked List | Slow and Fast Pointer | LeetCode Challenge](https://codingchallenge.hashnode.dev/day-8-linked-list-cycle-and-middle-of-the-linked-list-slow-and-fast-pointer-leetcode-challenge?utm_source=hashnode&utm_medium=feed) Restarting after long 2 min read · [codingchallenge.hashnode.dev](https://codingchallenge.hashnode.dev/day-8-linked-list-cycle-and-middle-of-the-linked-list-slow-and-fast-pointer-leetcode-challenge?utm_source=hashnode&utm_medium=feed) [Sartaj Ahmad Hajam](https://hashnode.com/@hajamsaj) · [Nov 30, 2025](https://hashnode.com/posts/30-days-of-terraform-aws-days-36-combined/692bff0c5fee9e53080ecf35) ### [30 Days of Terraform (AWS) — Days 3–6 (Combined)](https://awsterraform30days.hashnode.dev/30-days-of-terraform-aws-days-36-combined?utm_source=hashnode&utm_medium=feed) I’ve been busy the past few days so I’m combining Days 3–6 into one post. From Day 7 onward I’ll publish a separate post for each day again. Overview (what we cover in this post) Day 3 — AWS Authentication & S3 bucket basics (Terraform + AWS credent... 6 min read · [awsterraform30days.hashnode.dev](https://awsterraform30days.hashnode.dev/30-days-of-terraform-aws-days-36-combined?utm_source=hashnode&utm_medium=feed) [Sartaj Ahmad Hajam](https://hashnode.com/@hajamsaj) · [Nov 27, 2025](https://hashnode.com/posts/day-2-of-my-30daysofawsterraform-journey/6928767b717d100156de1229) ### [🚀 Day 2 of My #30DaysOfAWSTerraform Journey](https://awsterraform30days.hashnode.dev/day-2-of-my-30daysofawsterraform-journey?utm_source=hashnode&utm_medium=feed) Understanding Terraform Providers — The Real Bridge Between Terraform & AWS 3 min read · [awsterraform30days.hashnode.dev](https://awsterraform30days.hashnode.dev/day-2-of-my-30daysofawsterraform-journey?utm_source=hashnode&utm_medium=feed) [Yash Chavda](https://hashnode.com/@yashchavda) · [Sep 10, 2025](https://hashnode.com/posts/what-i-learned-from-failing-my-30-day-product-challenge/68c11d01c1eb2391389e3563) ### [What I Learned From Failing My 30-Day Product Challenge](https://yashchavda.hashnode.dev/what-i-learned-from-failing-my-30-day-product-challenge?utm_source=hashnode&utm_medium=feed) I tried to build a product in 30 days and failed halfway. Here’s what went wrong, what I learned, and why I’m still working on it — but with a lean MVP 2 min read · [yashchavda.hashnode.dev](https://yashchavda.hashnode.dev/what-i-learned-from-failing-my-30-day-product-challenge?utm_source=hashnode&utm_medium=feed) [Ayush](https://hashnode.com/@ayush-devhub) · [Aug 31, 2025](https://hashnode.com/posts/day-4-java-console-based-student-grade-manager/68b47a5cea40575f38d81241) ### [Day 4: Java Console Based Student Grade Manager](https://ayush-devhub.hashnode.dev/day-4-java-console-based-student-grade-manager?utm_source=hashnode&utm_medium=feed) What I Built Today Today, I built a console-based Student Grade using Java. This project uses an ArrayList, Hash Map and txt file to track grades. Users can perform the following operations: Add a student. Add subjects & marks for the respective st... 3 min read · [ayush-devhub.hashnode.dev](https://ayush-devhub.hashnode.dev/day-4-java-console-based-student-grade-manager?utm_source=hashnode&utm_medium=feed) [Ayush](https://hashnode.com/@ayush-devhub) · [Aug 30, 2025](https://hashnode.com/posts/day-3-java-console-based-expense-tracker/68b3302fbe5797713d096f4a) ### [Day 3: Java Console Based Expense Tracker](https://ayush-devhub.hashnode.dev/day-3-java-console-based-expense-tracker?utm_source=hashnode&utm_medium=feed) What I Built Today Today, I built a console-based Expense Tracker using Java. This project uses an ArrayList and CSV file to track expenses. Users can perform the following operations: Add expenses (category, amount, note, date). View all expenses.... 3 min read · [ayush-devhub.hashnode.dev](https://ayush-devhub.hashnode.dev/day-3-java-console-based-expense-tracker?utm_source=hashnode&utm_medium=feed) [Ayush](https://hashnode.com/@ayush-devhub) · [Aug 29, 2025](https://hashnode.com/posts/day-2-java-cli-based-library-book-tracker/68b1f955c8d8ccf512fad19a) ### [Day 2: Java CLI Based Library Book Tracker](https://ayush-devhub.hashnode.dev/day-2-java-cli-based-library-book-tracker?utm_source=hashnode&utm_medium=feed) What I Built Today Today I worked on a console-based Library Book Tracker. Users can: add books check books out return books list all books (both available & checked out) We use an ArrayList to keep track of books. What I Struggled With Fixing... 2 min read · [ayush-devhub.hashnode.dev](https://ayush-devhub.hashnode.dev/day-2-java-cli-based-library-book-tracker?utm_source=hashnode&utm_medium=feed)