Educational Codeforces Round 110 (Rated for Div. 2)

Solutions for Educational Codeforces Round 110 (Rated for Div. 2) (contest 1535). 2/6 problems verified against sample I/O. Difficulty range: 800-3000.

6 items

Educational Codeforces Round 110 (Rated for Div. 2)

Type: Div. 2 | Problems: 6 | Verified: 2/6 | Rating range: 800-3000 | Time: 44m 53s

Problem	Name	Rating	Tags	Solve Time	Verified
A	Fair Playoff	800	brute-force, implementation	6m 21s	✗
B	Array Reodering	900	brute-force, greedy, math	3m 59s	✓
C	Unstable String	1400	binary-search, dp, greedy	20m 6s	✓
D	Playoff Tournament	1800	data-structures, dfs-and-similar, dp	1m 5s	✗
E	Gold Transfer	2200	binary-search, data-structures, dp	7m 16s	✗
F	String Distance	3000	binary-search, brute-force, data-structures	6m 6s	✗

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CF 1535C - Unstable String

We are given a string containing '0', '1', and '?'. A substring is considered beautiful if we can replace every '?' independently with either 0 or 1 so that the resulting substring becomes an alternating binary string. In other words, neighboring characters must always differ.

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CF 1535F - String Distance

We are given a collection of strings of equal length, and our task is to quantify how "sortable into each other" they are using a specific operation. This operation allows us to take any contiguous substring in one string and sort its characters in ascending order.

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CF 1535E - Gold Transfer

I see what is happening. The actual output is empty. That usually happens when the code reads input correctly but never prints anything, which often occurs if we are using input = sys.stdin.

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CF 1535A - Fair Playoff

We have a mini playoff tournament with exactly four players. The first two face off, the last two face off, and the winners meet in the final. Each player has a unique skill value, and in any match the higher-skilled player always wins.

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CF 1535D - Playoff Tournament

The proposed solution does not answer the exercise at all. Exercise 4.3.2.7 asks for a derivation of an alternative form of equation (24) in the Chinese remainder conversion algorithm, followed by a discussion of the computational advantages and disadvantages of storing the…

Practice › Codeforces Solutions › Educational Codeforces Round 110 (Rated for Div. 2) ›

CF 1535B - Array Reodering

We are given an array of integers and may permute it however we like. After choosing an ordering, a pair of positions $(i,j)$ with $i<j$ is called good if $$gcd(ai, 2aj) 1.$$ The task is to maximize the number of good pairs. The input contains multiple test cases.