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### Motarack's blog

By Motarack, history, 11 months ago, ,

Some problems don't have a tutorial yet, those should be added later.

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Short and precise explanation by praran26 can be found here.

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• +37

 » 11 months ago, # | ← Rev. 2 →   +16 So, just to confirm: The rectangle (mirror) in problem F must be axis-aligned, right? Is it possible to add that to the problem statement?
•  » » 11 months ago, # ^ |   +24 Yes, I will do that, sorry for the confusion.
•  » » » 11 months ago, # ^ |   +19 No worries. Thanks for the nice contest!
 » 11 months ago, # |   0 Could you share a solution code for problem A ? I can't debug my code....thanks
•  » » 11 months ago, # ^ |   +3 Added above.
 » 11 months ago, # |   0 Is anyone of these problems intended for Div2 guys?
•  » » 11 months ago, # ^ |   0 As mentioned in the announcement the contest is intended for contestants with rating in the range [1600, 2600].
 » 10 months ago, # | ← Rev. 2 →   0 For Problem D. Two Sequences Why this code is giving WA as verdict on Test Case 2: vectorv1(n+1),v2(n+1); REP(i,n){ cin>>v1[i]; } REP(i,n){ cin>>v2[i]; } bool flag = 1; REP(i,n){ long x = v1[i], y = v2[i]; if(abs(x-y)<=k) flag &= 1; else {flag = 0;break;} } if(flag == 0) cout<<"NO\n"; else cout<<"YES\n";
•  » » 10 months ago, # ^ |   0 make sure to read the statement correctly, if you still don't know why it's wrong then try manually some random small cases.
•  » » » 10 months ago, # ^ |   0 Got it, reading it incorrectly We can compare the elements in any order. Thanks
 » 2 months ago, # | ← Rev. 2 →   0 Problem C (Bonus):Coefficient of $a_k = \frac{(k+1)\binom{n+1}{k+1}}{n-k+1}-1$ will do the trick.