Codeforces Round 590 (Div. 3)

6 problems from Codeforces Round 590 (Div. 3) (contest 1234), difficulty 800-2000. 5/6 solutions verified against sample I/O.

6 items

Codeforces Round 590 (Div. 3)

Div. 3 | 6 problems | 5/6 verified | Difficulty 800-2000 | 19m 19s

#	Problem	Rating	Tags	Accepted	Time	✓
A	Equalize Prices Again	800	math	29,550	4m 6s	✓
B1	Social Network (easy version)	1000	implementation	19,765	1m 25s	✓
B2	Social Network (hard version)	1300	data-structures, implementation	18,442	5m 19s	✓
C	Pipes	1500	dp, implementation	13,484	3m 46s
D	Distinct Characters Queries	1600	data-structures	18,582	2m 57s	✓
E	Special Permutations	2000	math	2,977	1m 46s	✓

Practice › Codeforces Solutions › Codeforces Round 590 (Div. 3) ›

CF 1234B2 - Social Network (hard version)

We are simulating a dynamic list of conversations ordered by “recency of appearance on screen”, with a hard cap on how many conversations can be shown at once. Each incoming message is tied to a single friend ID, and every ID corresponds to exactly one conversation.

Practice › Codeforces Solutions › Codeforces Round 590 (Div. 3) ›

CF 1234C - Pipes

We are given a grid with two rows and n columns, where each cell contains a pipe segment of one of six possible shapes. Each pipe can be rotated in 90-degree steps any number of times, so effectively each piece can be reoriented into any of its rotational variants.

Practice › Codeforces Solutions › Codeforces Round 590 (Div. 3) ›

CF 1234D - Distinct Characters Queries

We are maintaining a string of lowercase letters under two kinds of operations. One operation modifies a single position in the string, changing its character.

Practice › Codeforces Solutions › Codeforces Round 590 (Div. 3) ›

CF 1234A - Equalize Prices Again

We are given several independent scenarios. In each one, a shop has a list of item prices. The goal is to replace all of these different prices with a single uniform price so that selling all items at this single price does not reduce the total revenue compared to the original…

Practice › Codeforces Solutions › Codeforces Round 590 (Div. 3) ›

CF 1234E - Special Permutations

We are given a sequence x of length m. For every value i from 1 to n, we construct a special permutation: pi = [i, 1, 2, ..., i-1, i+1, ..., n] This permutation differs from the identity permutation only because the value i has been moved to the front.

Practice › Codeforces Solutions › Codeforces Round 590 (Div. 3) ›

CF 1234B1 - Social Network (easy version)

We are simulating the behavior of a smartphone chat interface. The smartphone screen can show at most $k$ conversations. Each incoming message comes from a friend identified by a unique ID. If a conversation with that friend is already on the screen, the screen does not change.