wuhudsm's blog

By wuhudsm, history, 14 months ago, In English

A

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B

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C

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D

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E

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F

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14 months ago, # |
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B. If $$$n=1$$$, answer 1 if $$$con(k,k)$$$ is prime?

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    14 months ago, # ^ |
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    In fact when $$$k>1$$$,$$$con(k,k)$$$ is always not a prime.

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      14 months ago, # ^ |
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      wow, how to prove it?

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        14 months ago, # ^ |
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        For $$$k>1,con(k,k)$$$ has a divisor $$$10^{\lfloor log_{10}(k) \rfloor}+1$$$.

        For example,$$$123123$$$ has a divisor $$$1001(123*1001=123123)$$$.

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      14 months ago, # ^ |
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      oh, ok; $$$con(k,k)$$$ is a $$$k+ 10^x * k$$$

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14 months ago, # |
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Very interesting contest <3

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14 months ago, # |
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Didn't get the editorial of C,can anyone tell their approach of how they solved C?

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    14 months ago, # ^ |
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    Editorial of C updated :)

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      14 months ago, # ^ |
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      In Problem C : What is the condition for -1, Can you explain it, please ? According to editorial, we can always make 2max(ai)≤Σai in atmost 2 operation of increasing minimum values by 26, then what is the case, when -1 comes ?

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        14 months ago, # ^ |
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        The unsolvable situation only occurs in $$$n=2,s_1 \neq s_2$$$.

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14 months ago, # |
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Couldnt understand C

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14 months ago, # |
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Great Problemset. Enjoyable Round. Thanks for this :)

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14 months ago, # |
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14 months ago, # |
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can someone explain A? :)

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14 months ago, # |
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Interesting problem F

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14 months ago, # |
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Memory Limit is too low for Python solutions to pass Problem D.