_SmallBrain_'s blog

What's the best problem you have seen!
By _SmallBrain_, history, 4 weeks ago, In English

Feel free to share some of your best solved problems that you felt interesting to solve or taught you something new in range of 1800-2200.

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4 weeks ago, # |
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I liked this problem although it is kind of classical but good to solve https://mirror.codeforces.com/contest/1155/problem/D

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4 weeks ago, # |
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2036F - XORificator 3000. Easy to think of the approach until you realize

SPOILER ALERT - DON'T LOOK UNTIL YOU GIVE IT A SHOT AND FRUSTATE YOURSELF ENOUGH
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    4 weeks ago, # ^ |
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    long long works , just use (1ll<<i) instead of (1<<i) i guess

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      4 weeks ago, # ^ |
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      Just submitted the editorial code replacing #define int unit64_t with #define int long long and it gave WA on 1. 293274046

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        4 weeks ago, # ^ |
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        Replace (1<<i) with (1ll<<i) and try

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        4 weeks ago, # ^ |
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        In this editorial solution it does not work i guess, because it is using the properties of unsigned for shifting (maybe because test case 1 is wrong even though no overflow), but you need not use unsigned integers just do normally and take care if the value goes negative somewhere

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          4 weeks ago, # ^ |
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          Can you elaborate a little more about those properties like what makes it different from long long? I thought the only difference between these two is the range of numbers they store.

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    4 weeks ago, # ^ |
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    True!

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4 weeks ago, # |
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One of the bests i solved
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4 weeks ago, # |
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https://mirror.codeforces.com/problemset/problem/1916/D

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4 weeks ago, # |
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Another classical but rarely used idea: 1155E - Guess the Root.

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4 weeks ago, # |
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This one changed my life a few hours ago https://mirror.codeforces.com/contest/280/problem/C

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4 weeks ago, # |
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the best problem I've seen? the one I set: 2031E - Penchick and Chloe's Trees

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4 weeks ago, # |
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1844G - Tree Weights and 1770F - Koxia and Sequence. The coolest problems I have seen.

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4 weeks ago, # |
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https://mirror.codeforces.com/problemset/problem/1497/C2 https://mirror.codeforces.com/problemset/problem/1527/C THESE ARE OF NUMBER THEORY

https://mirror.codeforces.com/problemset/problem/1971/G THIS ONE IS BITMASK

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4 weeks ago, # |
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The most difficult to prove (solution/checker/etc) looks the best, so that would be e-olymp/3673, but they changed design so..

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4 weeks ago, # |
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ask this to pienotpi as he is the best coder in India and he lives 4 rooms before your room

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