Codeforces Round 791 (Div. 2)

Solutions for Codeforces Round 791 (Div. 2) (contest 1679). 5/6 problems verified against sample I/O. Difficulty range: 900-2600.

6 items

Codeforces Round 791 (Div. 2)

Type: Div. 2 | Problems: 6 | Verified: 5/6 | Rating range: 900-2600 | Time: 12m 21s

Problem	Name	Rating	Tags	Solve Time	Verified
A	AvtoBus	900	brute-force, greedy, math	1m 37s	✓
B	Stone Age Problem	1200	data-structures, implementation	1m 30s	✓
C	Rooks Defenders	1400	data-structures, implementation	1m 23s	✓
D	Toss a Coin to Your Graph...	1900	binary-search, dfs-and-similar, dp	2m 3s	✓
E	Typical Party in Dorm	2400	bitmasks, combinatorics, dp	2m 13s	✗
F	Formalism for Formalism	2600	bitmasks, dp, math	3m 35s	✓

Practice › Codeforces Solutions › Codeforces Round 791 (Div. 2) ›

CF 1679F - Formalism for Formalism

We are given a length $n$ string of decimal digits, and a set of constraints between digits in the form of allowed adjacent swaps.

Practice › Codeforces Solutions › Codeforces Round 791 (Div. 2) ›

CF 1679E - Typical Party in Dorm

We are given a string of length n composed of the first 17 lowercase letters (a through q) and question marks. Each question mark acts as a wildcard that can be replaced by a letter from a specific set provided in a query.

Practice › Codeforces Solutions › Codeforces Round 791 (Div. 2) ›

CF 1679D - Toss a Coin to Your Graph...

The problem gives a directed graph where each vertex has a positive integer value. Masha can place a coin on any vertex, and then move it along the graph edges exactly $k-1$ times. Every time the coin visits a vertex, the vertex’s number is recorded in a notebook.

Practice › Codeforces Solutions › Codeforces Round 791 (Div. 2) ›

CF 1679A - AvtoBus

We are asked to determine how many buses a fleet could have given the total number of wheels. Each bus comes in one of two types: two-axle buses with 4 wheels and three-axle buses with 6 wheels.

Practice › Codeforces Solutions › Codeforces Round 791 (Div. 2) ›

CF 1679B - Stone Age Problem

We are given an array of integers and a sequence of queries. Each query either replaces a single element in the array with a new value or replaces every element in the array with the same value. After each query, we need to report the sum of the array.

Practice › Codeforces Solutions › Codeforces Round 791 (Div. 2) ›

CF 1679C - Rooks Defenders

We are asked to simulate a sequence of operations on an $n times n$ chessboard involving rooks. Each rook attacks its entire row and column.