Daily (117 day streak)

Interesting problem, I wouldn't say it is hard, simulation will work, the trick here to write a good simulation, or figure out smart algo

https://leetcode.com/problems/count-collisions-on-a-road/description/?envType=daily-question&envId=2025-12-04

#daily #medium

Daily (118 day streak)

Happy Friday, enjoy, 3 minutes easy problem

https://leetcode.com/problems/count-partitions-with-even-sum-difference/description/?envType=daily-question&envId=2025-12-05

#daily #easy

Video is out:

https://youtu.be/-5laXGtKInU?si=uOnka_pBomBWs7r2

Daily (119 day streak)

This could have been typical dynamic programming problem for 5 mins, BUT, by 38% acceptance rate + people scresming that it should be hard one - now it is not that easy.

Spoiler, O(n^2) will give TLE. We need something more optimized here. Didn't come up with it yet, will do tomorrow after sleep

https://leetcode.com/problems/count-partitions-with-max-min-difference-at-most-k/description/?envType=daily-question&envId=2025-12-06

#daily #medium

Daily (120 day streak)

This easy feels like blessing after yesterday's question.

https://leetcode.com/problems/count-odd-numbers-in-an-interval-range/description/?envType=daily-question&envId=2025-12-07

#daily #easy

Daily (121 day streak)

Happy monday, easy problem.

https://leetcode.com/problems/count-square-sum-triples/description/?envType=daily-question&envId=2025-12-08

#daily #easy

Approve this approach XDDDD. Now similar cases in real life xD

Daily (122 day streak)

Happy Tuesday, actually amazing problem, exactly how medium should be. Enjoyed it, however I have read the first hint to get the idea behind the map usage.


https://leetcode.com/problems/count-special-triplets/description/?envType=daily-question&envId=2025-12-09


#daily #medium

Youtube introduced A/B testing for titles, and I guess thumbnails. Niiiice. Extremely good feature

Daily (123 day streak)

Happy Wednesday. Today is interesting problem. The kind of problem, when you need to figure out few things and then solution is really trivial. For me was a bit hard to understand what is needed.

Initially I thought that we count dependency chain. E.g. in the 1st example, [0,1,2] => means pc1 was unlocked from pc0, pc2 was unlocked from pc1. IT IS NOT.
THE ASK HERE IS to count the order of computers being unlocked. So [0,1,2] => also means pc1 was unlocked from pc1, and pc2 was unlocked from pc0.

Testcase [2,68,61], expected number of permutations is 2

https://leetcode.com/problems/count-the-number-of-computer-unlocking-permutations/description/?envType=daily-question&envId=2025-12-10

#daily #medium

UPD:

permutations *= cnt -> 3000ms
permutations = permutations * cnt -> 3000ms
permutations = permutations * cnt % mod -> 17ms
permutations = (permutations * cnt) % mod -> 17ms
permutations *= cnt % mod -> 3000ms

For now seems strange

Actually makes sense. The smaller the numbers the quicker the multiplication.

p *= cnt % mod will be converted to p = p * (cnt % mod). So basically we will always work with bigger numbers

Order of operations isfrom left to right for ‘*’ and ‘%’ as they are same “rank”

Daily (124 day streak)

Happy Thursday. Amazing problem, I love problems that are representing some abstract model, that you can imagine, or even better - real world model, rather than just some numbers. Today is exactly that type of problems

https://leetcode.com/problems/count-covered-buildings/description/?envType=daily-question&envId=2025-12-11

#daily #medium

Fun fact, did you know you can add contributions/commits to github for the past and for future days. E.g. just added for 24th of Dec.

My ex techlead has shared the fun repo, and I was really doubting how it can add for the past or for the future, but it can for new empty repo

https://github.com/Shpota/github-activity-generator

I love Google ecosystem for personal use, Tasks, Calendar, Keep (notes), Drive/Docs, etc.

The only one thing I was not happy about Google Notes (Keep) is rich text editing (bold, italic formats, headings, etc).

THEY HAVE ADDED IT!!!

Was waiting for it for 3-4 years. On top of that every now and then I see improvements and new features for Google Tasks.

Love Google. At some point I will be hired there. Want to work on some of these personal / time management tools.

Daily (125 day streak)

Actually nice problem. Feels like some version of real engineering problem that somebody had.

https://leetcode.com/problems/count-mentions-per-user/description/?envType=daily-question&envId=2025-12-12

#daily #medium

Daily (126 day streak)

Happy Saturday. Today is easy, so few mins problem - get your coin.

https://leetcode.com/problems/coupon-code-validator/?envType=daily-question&envId=2025-12-13

#daily #easy