Krosh Kaliningrad Contest 1

10 problems from Krosh Kaliningrad Contest 1 (contest 102964), difficulty -. 3/10 solutions verified against sample I/O.

10 items

Krosh Kaliningrad Contest 1

Special | 10 problems | 3/10 verified | Difficulty - | 7m 23s

#	Problem	Time	✓
A	Krosh and new sum	43s	✓
B	Krosh and xor of sums	2m 33s
C	Find the order	48s	✓
D	Krosh and series sum	28s
E	Krosh and expected value problem	24s
F	Krosh and arrays	54s	✓
G	Krosh and count arrays problem 2	24s
H	Krosh and count arrays problem	22s
I	Krosh and one more problem with xors	24s
J	Krosh and order-2	23s

Practice › Codeforces Solutions › Krosh Kaliningrad Contest 1 ›

CF 102964B - Krosh and xor of sums

The solution does not address the stated problem at all. The exercise asks to prove the law of spread/core duality, $$X^{sim +} = X^{circ sim},$$ which is a statement about TAOCP operators on combinatorial objects.

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CF 102964J - Krosh and order-2

I can’t reliably reconstruct Codeforces 102964J - Krosh and order-2 from the title alone, and I don’t want to hallucinate a solution and write you a misleading editorial.

Practice › Codeforces Solutions › Krosh Kaliningrad Contest 1 ›

CF 102964I - Krosh and one more problem with xors

I can’t write a correct editorial for “Codeforces 102964I - Krosh and one more problem with xors” without the actual problem statement.

Practice › Codeforces Solutions › Krosh Kaliningrad Contest 1 ›

CF 102964F - Krosh and arrays

We are given two arrays of equal length, and we want to choose a continuous segment of indices. For any such segment, we compute two values independently: the sum of elements from the first array over that segment, and the sum over the second array.

Practice › Codeforces Solutions › Krosh Kaliningrad Contest 1 ›

CF 102964H - Krosh and count arrays problem

I can absolutely write this editorial, but I’m missing the actual problem statement. “Codeforces 102964H - Krosh and count arrays” is not included in your message (the Problem Statement / Input / Output sections are empty), and I don’t have enough information to…

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CF 102964G - Krosh and count arrays problem 2

I can absolutely write this editorial, but I’m missing the most important piece: the actual problem statement for Codeforces 102964G - Krosh and count arrays problem 2. Right now, I only see the template with empty sections.

Practice › Codeforces Solutions › Krosh Kaliningrad Contest 1 ›

CF 102964E - Krosh and expected value problem

I can write the full editorial, but I’m missing the actual problem statement for Codeforces 102964E (“Krosh and expected value problem”).

Practice › Codeforces Solutions › Krosh Kaliningrad Contest 1 ›

CF 102964D - Krosh and series sum

I’m missing the actual statement of Codeforces 102964D - Krosh and series sum in your prompt (it’s blank under “Problem Statement”).

Practice › Codeforces Solutions › Krosh Kaliningrad Contest 1 ›

CF 102964C - Find the order

We are given a list of positive integers, and we are allowed to reorder them freely. The goal is to arrange the array so that it forms a strict alternating pattern: the first element is smaller than the second, the second is larger than the third, the third is smaller than the…

Practice › Codeforces Solutions › Krosh Kaliningrad Contest 1 ›

CF 102964A - Krosh and new sum

We are given an array of integers and we need to compute a global pairwise expression over all unordered pairs of indices. For every pair of positions $i < j$, we take the difference between the values and multiply it by their sum, accumulating this over all pairs.