Errichto's blog

TCO 2019 Round 4
By Errichto, 5 years ago, In English

I think that all problems looked awful at the first sight but actually all were quite cool :O

editorial (was posted as announcement after the round)

Congratulations to advancers! Results screenshot below (top10 gets to the finals + some early advancers from previous rounds).

results
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5 years ago, # |
← Rev. 2   Vote: I like it +21 Vote: I do not like it

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5 years ago, # |
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Can anyone explain how to generate all numbers efficiently in easy problem :)

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    5 years ago, # ^ |
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    It's easy to see that almost any answer has all digits in non decreasing order, therefore you can generate them storing current length and last digit.

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      5 years ago, # ^ |
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      10

      Spoiler
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5 years ago, # |
← Rev. 2   Vote: I like it +16 Vote: I do not like it

250 can be solved by brute force searching < 1e7, if not found use oeis_seq (goal — base0)

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5 years ago, # |
← Rev. 2   Vote: I like it +30 Vote: I do not like it

Why aren't ratings being updated? The round was rated, right? hmehta?

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    5 years ago, # ^ |
      Vote: I like it +5 Vote: I do not like it

    Sorry, there was a slight delay coz of the Japan Regional Round Results to be published before this round but they were updated a day later :)

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