Tanzim_bn's blog

Problem of the Year 2024
By Tanzim_bn, history, 4 hours ago, In English

As 2024 nears its end, let’s share the problems we enjoyed the most this year so far! Drop the problem name, link and what made it special (optional).

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4 hours ago, # |
  Vote: I like it +10 Vote: I do not like it

2044F - Easy Demon Problem Quite an interesting problem, looked really hard but had an easy mathematical solution (Do give it a try if you haven't).

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    2 hours ago, # ^ |
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    Would you mind giving some hints about it?

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      88 minutes ago, # ^ |
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      Think about how you could decompose the query that you have been given into parts that you can correlate with the orignal input.

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4 hours ago, # |
  Vote: I like it +15 Vote: I do not like it

1933E. Xor-Grid Problem It demonstrates the magical nature of XOR operations, completing the missing rows and columns in an array.

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3 hours ago, # |
  Vote: I like it +6 Vote: I do not like it

1919D — 01 Tree Everything fits so nicely together!

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3 hours ago, # |
  Vote: I like it +4 Vote: I do not like it

1878F - Vasilije Loves Number Theory

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2 hours ago, # |
  Vote: I like it +6 Vote: I do not like it

2029C - New Rating Although dp is easier to think here, the bin search solution is really satisfying.

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112 minutes ago, # |
  Vote: I like it +3 Vote: I do not like it

1843E — Tracking Segments binary search on the prefix sum!

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64 minutes ago, # |
  Vote: I like it +1 Vote: I do not like it

https://codeforces.net/contest/1931/problem/F It was such a nice thing to use cycle detection in a statement like this.

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36 minutes ago, # |
  Vote: I like it +8 Vote: I do not like it

Universal Cup 3.11 O - New School Term

I enjoyed being trolled by this problem. The final observation is so natural, yet so invisible. As far as I know, some LGMs were also trolled.

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34 minutes ago, # |
← Rev. 2   Vote: I like it +3 Vote: I do not like it

1977D - XORificator never seen this trick before and thought it was unsolvable before seeing the tutorial

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24 minutes ago, # |
  Vote: I like it 0 Vote: I do not like it

https://codeforces.net/problemset/problem/2042/E

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24 minutes ago, # |
← Rev. 2   Vote: I like it +1 Vote: I do not like it

ARC171E — Rookhopper's Tour

The setting feels very chaotic to me initially, but after thinking it though, it turns out there exist an elegant way to analysis the problem model very simply to make it solvable. It's just... astonishing!

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