Codeforces Round 674 (Div. 3)

Solutions for Codeforces Round 674 (Div. 3) (contest 1426). 5/6 problems verified against sample I/O. Difficulty range: 800-2000.

6 items

Codeforces Round 674 (Div. 3)

Type: Div. 3 | Problems: 6 | Verified: 5/6 | Rating range: 800-2000 | Time: 14m 3s

Problem	Name	Rating	Tags	Solve Time	Verified
A	Floor Number	800	implementation, math	5m 28s	✗
B	Symmetric Matrix	900	implementation	3m 44s	✓
C	Increase and Copy	1100	binary-search, constructive-algorithms, math	1m 24s	✓
D	Non-zero Segments	1500	constructive-algorithms, data-structures, greedy	1m 11s	✓
E	Rock, Paper, Scissors	1800	brute-force, constructive-algorithms, flows	1m 6s	✓
F	Number of Subsequences	2000	combinatorics, dp, strings	1m 10s	✓

Practice › Codeforces Solutions › Codeforces Round 674 (Div. 3) ›

CF 1426A - Floor Number

The problem asks us to find the floor number of a given apartment in a building with a slightly unusual layout. The first floor always has exactly two apartments, and every subsequent floor has the same number of apartments, which is given by $x$.

Practice › Codeforces Solutions › Codeforces Round 674 (Div. 3) ›

CF 1426F - Number of Subsequences

We are given a string composed of the letters "a", "b", "c", and the special character "?". Each "?" can be replaced independently by any of the letters "a", "b", or "c".

Practice › Codeforces Solutions › Codeforces Round 674 (Div. 3) ›

CF 1426B - Symmetric Matrix

We are asked to determine whether it is possible to tile an (m times m) square using (2 times 2) tiles so that the resulting square is symmetric with respect to its main diagonal. Each tile has fixed numbers in its four cells, and rotations are not allowed.

Practice › Codeforces Solutions › Codeforces Round 674 (Div. 3) ›

CF 1426E - Rock, Paper, Scissors

Alice and Bob are planning to play a fixed number of rounds of Rock, Paper, Scissors. Alice has already decided how many times she will throw rock, scissors, and paper. Bob has made the same type of plan.

Practice › Codeforces Solutions › Codeforces Round 674 (Div. 3) ›

CF 1426D - Non-zero Segments

We are given a sequence of nonzero integers and are allowed to insert arbitrary integers anywhere between adjacent elements. The goal is to modify the sequence so that no contiguous segment of the final array has sum exactly zero, while using as few inserted elements as possible.

Practice › Codeforces Solutions › Codeforces Round 674 (Div. 3) ›

CF 1426C - Increase and Copy

We start with a single-element array containing the number 1. We are allowed two operations: either increment any element by 1 or copy any element to the end of the array.