Codeforces Round 879 (Div. 2)

Solutions for Codeforces Round 879 (Div. 2) (contest 1834). 2/6 problems verified against sample I/O. Difficulty range: 800-2500.

6 items

Codeforces Round 879 (Div. 2)

Type: Div. 2 | Problems: 6 | Verified: 2/6 | Rating range: 800-2500 | Time: 9m 54s

Problem	Name	Rating	Tags	Solve Time	Verified
A	Unit Array	800	greedy, math	1m 53s	✗
B	Maximum Strength	1000	greedy, math	1m 38s	✓
C	Game with Reversing	1200	games, greedy, math	1m 43s	✗
D	Survey in Class	1900	brute-force, data-structures, greedy	1m 52s	✗
E	MEX of LCM	2300	binary-search, data-structures, implementation	1m 15s	✓
F	Typewriter	2500	brute-force, math	1m 33s	✗

Practice › Codeforces Solutions › Codeforces Round 879 (Div. 2) ›

CF 1834D - Survey in Class

We have a classroom of n students and m topics. Each student has learned a continuous range of topics, from li to ri. When the teacher asks about a topic, each student either raises or lowers their hand depending on whether they know the topic.

Practice › Codeforces Solutions › Codeforces Round 879 (Div. 2) ›

CF 1834F - Typewriter

The solution correctly identifies what the “improved KS test” is trying to do: it replaces the unweighted empirical process by a variance-stabilized version, dividing by the binomial standard deviation $sqrt{F(x)(1-F(x))}$.

Practice › Codeforces Solutions › Codeforces Round 879 (Div. 2) ›

CF 1834E - MEX of LCM

We are asked to find the smallest positive integer that cannot appear as the least common multiple of any contiguous subarray of a given array. The input consists of multiple test cases.

Practice › Codeforces Solutions › Codeforces Round 879 (Div. 2) ›

CF 1834A - Unit Array

Investigate the "improved" KS test suggested in the answer to exercise 6. Let $X1, X2, ldots, Xn$ be independent observations drawn from a continuous distribution function $F(x)$.

Practice › Codeforces Solutions › Codeforces Round 879 (Div. 2) ›

CF 1834C - Game with Reversing

We are given two strings of equal length. In a turn-based game, Alice can modify any single character in either string, while Bob can take an entire string and reverse it.

Practice › Codeforces Solutions › Codeforces Round 879 (Div. 2) ›

CF 1834B - Maximum Strength

Fedya has a collection of materials, each represented by a positive integer indicating its strength. He can combine two materials into a weapon, and the weapon's strength is the sum of the absolute differences between corresponding digits of the two numbers, aligned from the…