1900_mashups's blog

By 1900_mashups, history, 23 months ago, In English

hello codeforces,

i am glad to invite you all to my practice mashups, which i am going to start from tomorrow.
it is mainly prepared for those who aspire to become masters (be it candidates, experts, div 2 guys, div 3 guys, div 4 guys, or even an inactive master). so, the mashups will have mostly 1900+ rated problems.
i will share the mashup links through the comments of this blog, so that everyone can access it.

excited to see you guys at the standings.

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23 months ago, # |
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Thanks

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

the third practice mashup will start on 8th July 2022, today at 10:35 UTC.

number of problems: 3
duration of mashup: 1:30 hrs
ratings of problems: 800, 1600, 1900

registration is open.

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    23 months ago, # ^ |
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    So are you just picking any problem of given difficulty or hand-picking problems?

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23 months ago, # |
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Nice initiative. I liked ADE2.

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23 months ago, # |
Rev. 2   Vote: I like it +3 Vote: I do not like it

ADE (3) practice mashup will start on 12 July 2022 at 5:35 UTC.

number of problems: 3
duration of mashup: 2:30 hrs
ratings of problems: 800, 1900, 2000

UPD: registration is open;

PS: my intern drive is ongoing, so i wasn't preparing mashups for few days.

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22 months ago, # |
Rev. 2   Vote: I like it +8 Vote: I do not like it

ADE (9) practice mashup will start on 3rd August 2022 at 10:05 UTC (15:35 IST).

number of problems: 3
duration of mashup: 2:30 hrs
ratings of problems: 800, 1900, 2000

registration is open;

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

ADE (10) Practice Mashup will start on 5th August 2022 at 10:05 UTC (15:35 IST).

Problems count: 3
Duration: 2:30 hrs
Ratings of problems: 800, 1900, 2000

Registration link: https://codeforces.com/contestInvitation/5c3004a99447d5cd5d870fb59112e4d13dd0c274

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22 months ago, # |
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ADE (11) Practice Mashup will start on 9th August 2022 at 09:35 UTC (15:05 IST).

Count of problems: 3
Duration: 2:30 hrs
Ratings of problems: 800, 1900, 2000

Registration link: https://codeforces.com/contestInvitation/361449889e11b8e91fdc90247d09ee30f76948f1

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22 months ago, # |
Rev. 2   Vote: I like it +8 Vote: I do not like it

ADE (12) Practice Mashup will start on 10th August 2022 at 10:05 UTC (15:35 IST).

Count of problems: 3
Duration: 2:30 hrs
Ratings of problems: 800, 1900, 2000

Registration link: https://codeforces.com/contestInvitation/54cd64d50d981b42a253ac7414f7e9541c024cf8

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19 months ago, # |
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Today's (28th Nov 22) practice mashup will start at 05:35 UTC (11:05 IST).

Count of problems: 3
Duration: 2:30 hrs
Ratings of problems: 800, 1900, 2000

Registration link: https://codeforces.com/contestInvitation/3bb9cb14905201ab30618cafdc06f6808415167a

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18 months ago, # |
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Today's (3rd Dec 22) practice mashup will start at 06:35 UTC (12:05 IST).

Count of problems: 3
Duration: 2:00 hrs
Ratings of problems: 800, 1900, 2000

Registration link: https://codeforces.com/contestInvitation/090d848c8efd9489db266378175db6c1f8d462b4

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18 months ago, # |
  Vote: I like it +27 Vote: I do not like it

Glad to inform you guys, that I have finally became a master. Now, I don't know what to do next, maybe I could come up with a new blog "Mashups for aspiring IMs" ? Lol.

Do anyone of you have any other interesting ideas for me or the community ?

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18 months ago, # |
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can someone explain problem c of 11th Dec that why is the probability of a student who reads message mi
is ki/t if t>ki ?
shouldn't it be ncr(t,ki-1)/ncr(t,ki) where we are fixing the message which the ith student to read.
In question it was given all k sets are equiprobable but I couldn't understand why it is the reason for probability as ki/t ?
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    18 months ago, # ^ |
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    Sorry for late reply, but it's good you asked this. Actually, when you're fixing the message $$$m_i$$$, then you have to choose rest $$$k_i - 1$$$ messages out of $$$t - 1$$$ messages (note that total messages would also decrease by 1). So, the numerator in your formula was wrong.

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      18 months ago, # ^ |
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      Thanks for bringing me to peace with this question. Guess newbie things.. I mess up with indexing stuff

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      18 months ago, # ^ |
      Rev. 3   Vote: I like it +8 Vote: I do not like it

      Thanks great mashups for beg