I'm about to start my second year of college and began learning data structures and algorithms during my break after first year. I'm currently following Striver's A2Z sheet and am nearly finished with the arrays section. People often say that recognizing patterns is important and that you should solve several problems based on the same technique.
Is the A2Z sheet enough by itself, or should I find additional problems for each pattern? Also, what's the most effective way to revise: solving unfamiliar problems, repeating previously solved ones after a gap, or writing down patterns and reviewing them regularly? I'd especially appreciate recommendations for free practice resources and advice on whether I'm progressing in the right way.
2 Answers
Use the sheet alongside the explanations, but focus on solving rather than just watching videos. Once you’re comfortable attempting problems, timed contests are a good way to build speed and recognize patterns under pressure. A curated set such as Blind 75 can also be useful for later revision.
You don’t need to solve dozens of nearly identical questions for every pattern. Revisit important problems with gaps between attempts, and keep short notes containing the idea, when to use it, common mistakes, and complexity. It’s also worth becoming comfortable with standard templates such as BFS, DFS, sorting, binary search, and basic dynamic programming so implementation doesn’t distract you during harder problems.
The sheet is a strong starting point, and you probably don’t need another large list immediately. The most useful revision happens when you return to a problem after you’ve forgotten the solution. That shows whether you understood the approach or only remembered the steps. Repeating problems after a few days or weeks is useful, especially for patterns you struggled with.
I only have four array questions left. After finishing them, would it be useful to revisit the whole array section from the beginning?
I tried my first contest and solved two problems, but I spent nearly an hour stuck on the third. Is that a normal result while starting out?