A conversation about solving the Minimum Coin Combination problem that reveals why greedy algorithms sometimes fail—and how recognizing overlapping subproblems is the foundation of dynamic programming thinking.
A conversation about solving the LRU Cache problem that reveals one of the most elegant hybrid data structure designs—and why sometimes the "crazy" idea of combining two data structures is actually brilliant.
A conversation about solving the Widest Binary Tree Level problem that reveals how mathematical position formulas and DFS traversal create an elegant solution—and why we need to track both min and max positions at each level.
A conversation about solving the Subarray Sum Equals K problem that reveals how cumulative sums and hashmaps create an elegant O(n) solution—and why we need that mysterious map.put(0, 1) initialization.
I just made a commit, so why does VS Code still show that asterisk (*) on my branch name? A debugging journey through Git's "deleted" file status and what to do about it.
A conversation between two engineers about the Range Sum Query problem that reveals why some algorithmic techniques exist—and when they actually matter.
Frontend Dev: "I just finished working on my frontend branch and want to merge it into main. Someone told me to use rebase, but when I ran git rebase main, it said 'Current branch frontend is up to date.' What does that mean? Should I use merge instead?"
Git Mentor: "Ah, this is one of the most confusing topics in Git! Let me show you the difference between fast-forward merge and rebase, and when to use each one. Your 'up to date' message actually tells us something important!"
Backend Dev: "I just created a Postman collection in my backend worktree, and now Git is showing the entire postman/ folder as untracked files! I thought API testing folders were supposed to be gitignored automatically?"
DevOps Mentor: "Ah, you've discovered one of the subtle quirks of Git worktrees! Even though worktrees share the same repository, they each need proper .gitignore configuration. Let me show you what's happening!"
Backend Dev: "I just successfully rebased my backend branch with 18 commits onto main! But when I try to push, Git says I need to force push. Why can't I just do a regular push? What happened to my commits?"
Git Mentor: "Ah! You've encountered one of Git's most important safety mechanisms. Let me show you exactly what happened during your rebase and why you now need force push!"
Backend Dev: "I just successfully rebased my backend branch onto main with 18 commits. So now my main branch has all my backend changes, right?"
Git Mentor: "Actually... no! Your backend branch is updated, but main still doesn't have your changes!"
Backend Dev: "WHAT?! But I thought rebase puts my commits on top of main? Isn't that the same thing?"
Git Mentor: "Ah! This is one of the most common misunderstandings about Git! Let me show you exactly what happened and why main still doesn't have your changes!"