Codeforces Beta Round 92 (Div. 1 Only)

Solutions for Codeforces Beta Round 92 (Div. 1 Only) (contest 123). 3/5 problems verified against sample I/O. Difficulty range: 1300-2500.

5 items

Codeforces Beta Round 92 (Div. 1 Only)

Type: Div. 1 | Problems: 5 | Verified: 3/5 | Rating range: 1300-2500 | Time: 14m 53s

Problem	Name	Rating	Tags	Solve Time	Verified
A	Prime Permutation	1300	implementation, number-theory, strings	2m 19s	✗
B	Squares	1800	math	5m 4s	✓
C	Brackets	2300	combinatorics, dp, greedy	2m 19s	✓
D	String	2300	string-suffix-structures	2m 32s	✓
E	Maze	2500	dfs-and-similar, dp, probabilities	2m 39s	✗

Practice › Codeforces Solutions › Codeforces Beta Round 92 (Div. 1 Only) ›

CF 123A - Prime Permutation

We are given a string s composed of lowercase letters, with length n. The task is to determine if we can rearrange the letters so that for every prime p less than or equal to n, all positions in the string that are multiples of p can contain the same character.

Practice › Codeforces Solutions › Codeforces Beta Round 92 (Div. 1 Only) ›

CF 123B - Squares

We move on an infinite grid of unit squares. From any square we may move one step up, down, left, or right. Some squares are marked as bad, and entering such a square costs one.

Practice › Codeforces Solutions › Codeforces Beta Round 92 (Div. 1 Only) ›

CF 123C - Brackets

We are filling an n × m grid with brackets. Every cell contains either "(" or ")". The grid is called valid if every monotone path from the top-left corner to the bottom-right corner forms a correct bracket sequence. A monotone path only moves right or down.

Practice › Codeforces Solutions › Codeforces Beta Round 92 (Div. 1 Only) ›

CF 123D - String

We are given a string s. For every substring x of s, we look at all positions where x appears inside s. Suppose these occurrences start at positions: $$p1 < p2 < dots < pk$$ The function F(s, x) counts how many contiguous segments we can choose from this ordered list of…

Practice › Codeforces Solutions › Codeforces Beta Round 92 (Div. 1 Only) ›

CF 123E - Maze

We are given a tree, and two independent probability distributions over its vertices. One distribution chooses the starting vertex of a DFS, the other chooses the target vertex where the search stops.