wuhudsm's blog

By wuhudsm, history, 6 months ago, In English

A

code
solution

B

code
solution

C

code
solution

D

code
solution

E

code
solution

F

code
solution
  • Vote: I like it
  • +20
  • Vote: I do not like it

»
6 months ago, # |
Rev. 2   Vote: I like it 0 Vote: I do not like it

B. If $$$n=1$$$, answer 1 if $$$con(k,k)$$$ is prime?

  • »
    »
    6 months ago, # ^ |
    Rev. 2   Vote: I like it 0 Vote: I do not like it

    In fact when $$$k>1$$$,$$$con(k,k)$$$ is always not a prime.

    • »
      »
      »
      6 months ago, # ^ |
        Vote: I like it +3 Vote: I do not like it

      wow, how to prove it?

      • »
        »
        »
        »
        6 months ago, # ^ |
          Vote: I like it +14 Vote: I do not like it

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

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

    • »
      »
      »
      6 months ago, # ^ |
        Vote: I like it +3 Vote: I do not like it

      oh, ok; $$$con(k,k)$$$ is a $$$k+ 10^x * k$$$

»
6 months ago, # |
  Vote: I like it +8 Vote: I do not like it

Very interesting contest <3

»
6 months ago, # |
  Vote: I like it +1 Vote: I do not like it

Didn't get the editorial of C,can anyone tell their approach of how they solved C?

  • »
    »
    6 months ago, # ^ |
      Vote: I like it 0 Vote: I do not like it

    Editorial of C updated :)

    • »
      »
      »
      6 months ago, # ^ |
      Rev. 2   Vote: I like it 0 Vote: I do not like it

      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 ?

      • »
        »
        »
        »
        6 months ago, # ^ |
          Vote: I like it 0 Vote: I do not like it

        The unsolvable situation only occurs in $$$n=2,s_1 \neq s_2$$$.

»
6 months ago, # |
  Vote: I like it +1 Vote: I do not like it

Couldnt understand C

»
6 months ago, # |
  Vote: I like it +8 Vote: I do not like it

Great Problemset. Enjoyable Round. Thanks for this :)

»
6 months ago, # |
  Vote: I like it 0 Vote: I do not like it
»
6 months ago, # |
  Vote: I like it 0 Vote: I do not like it

can someone explain A? :)

»
6 months ago, # |
  Vote: I like it +21 Vote: I do not like it

Interesting problem F

»
6 months ago, # |
  Vote: I like it 0 Vote: I do not like it

Where can i find the classic problem mentioned in C

»
6 months ago, # |
  Vote: I like it 0 Vote: I do not like it

Memory Limit is too low for Python solutions to pass Problem D.