Invitation to CodeChef Starters 171 (Rated upto 5 stars) | 29th Jan
We invite you to participate in CodeChef’s Starters 171, this Wednesday, 29th January, rated upto 5 stars (i.e. for users with rating < 2200).
Time: 8:00 PM — 10:00 PM IST
Joining us on the problem setting panel are:
Contest Admin, Statement Verifier and Text Editorialists: Nishank IceKnight1093 Suresh
Tester: Sushil SmolBrain Raaja.
Setters:shubham6105, ananydhamija507, Inferno_The_God.
Written editorials will be available for all on discuss.codechef.com. Pro users can find the editorials directly on the problem pages after the contest. The video editorials of the problems will be available only to Pro users.
Also, if you have some original and engaging problem ideas, and you’re interested in them being used in CodeChef's contests, you can share them here. Hope to see you participating.
Good Luck!
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Auto comment: topic has been updated by shubham6105 (previous revision, new revision, compare).
Why are Indian School Students not allowed for some of the competitions like AlgoUnlock?
Since it's a part of our college fest, you won't be eligible for round 2, though you can give online round 1 if you want.
Okay...thanks
Reminder: The contest will start in ~20min.
Five minutes passed but still no statement has loaded on my pc. My net issue or codechef server issue??
how reasonable is it to just assume that we should have $$$K <= N$$$ in problem A. Weird, but maybe I am completely misunderstanding the statement but I needed this $$$K <= N$$$ thing to get AC.
Strange, didn't know number of players getting eliminated could be more than there were already!!
I meant div2 A Swish Game.
And as I said, maybe I am misunderstanding the statement. But, in first sample, what is wrong with N = 3 being an answer ?
Swish Game?
I think so the problem is quite intuitive. Think as -
The game will end immediately when at least one of the following two conditions is met - Toofan has finished all the N rings; or It is impossible to win the game any more. This means it is impossible for Toofan to get at least K swishes, regardless of what he does with the remaining rings. Given that Toofan ended the game after exactly this sequence of M moves, what could the value of N be?
so we can see that game has ended but he hasn't been able to capture 4 rings, thus we say now he can't capture any more too. So find suitable n.
For n = 3 the game would have ended without string as k = 4 which isn't possible.
Oh, so the game wouldn't start if N=3. You're right. Thanks and apologies.
No problem. Happy to help!
Can anyone please tell how to check no. of redundant string.
no of strings respecting the constraints in both direction — no of strings that respect the constraints and are palindromes gives you the number of string that could be met both ways.
Half of them will be redundant
In problem D, it is counting the number of distinct pairs like [a,b,c,d] and [d,c,b,a] then if any pair is pairwise distinct then inner values can be anything but if same then inner values have to compute 2 cases. If this is the solution, I am getting WA on the last test case.
it is not true that x/2 % MOD == (x%MOD)/2 !
try setting mod to 2 000 000 014 and outputting your answer % mod/2
Wait wait. A value like $$$15$$$ can be represented like $$$((5 * 6)/2)\mod M$$$ what's wrong in this. Ultimately it's getting multiplied by 15 and no division inverse thingy can impact this.
Tough contest btw
i was unable to solve even two question of div2 in first hour of the contest,luckily i ended up solving 4 questions btw nice div2 C and D
Even though it wasn't rated for me, my rating dropped.
The contest was rated till 5 stars only,you changed the rating of 2200+ as well.Please check this.