Codeforces Round 137 (Div. 2)

Solutions for Codeforces Round 137 (Div. 2) (contest 222). 3/4 problems verified against sample I/O. Difficulty range: 1200-1900.

4 items

Codeforces Round 137 (Div. 2)

Type: Div. 2 | Problems: 4 | Verified: 3/4 | Rating range: 1200-1900 | Time: 6m 42s

Problem	Name	Rating	Tags	Solve Time	Verified
A	Shooshuns and Sequence	1200	brute-force, implementation	1m 25s	✓
B	Cosmic Tables	1300	data-structures, implementation	1m 33s	✓
C	Reducing Fractions	1800	implementation, math, number-theory	34s	✗
E	Decoding Genome	1900	dp, matrices	3m 10s	✓

Practice › Codeforces Solutions › Codeforces Round 137 (Div. 2) ›

CF 222A - Shooshuns and Sequence

We have an array of integers and a strange operation that keeps the array length unchanged. In one operation, we look at the current k-th element, append a copy of it to the end, then remove the first element.

Practice › Codeforces Solutions › Codeforces Round 137 (Div. 2) ›

CF 222B - Cosmic Tables

We have a matrix of integers and three kinds of operations applied to it repeatedly. One operation swaps two rows. Another swaps two columns. The third asks for the value currently visible at a specific row and column.

Practice › Codeforces Solutions › Codeforces Round 137 (Div. 2) ›

CF 222C - Reducing Fractions

This is a Type C - Optimization problem. The task is to determine the maximum number of intersections among perpendiculars drawn from each of five points to lines formed by the other four points.

Practice › Codeforces Solutions › Codeforces Round 137 (Div. 2) ›

CF 222E - Decoding Genome

We are asked to count the number of valid sequences of nucleotides of length n for a Martian DNA strand, given a total of m nucleotides and a list of forbidden consecutive pairs. Each nucleotide is represented by a letter from 'a' to 'z' and 'A' to 'Z' depending on its index.