Codeforces Round 765 (Div. 2)

Solutions for Codeforces Round 765 (Div. 2) (contest 1625). 2/6 problems verified against sample I/O. Difficulty range: 800-2800.

6 items

Codeforces Round 765 (Div. 2)

Type: Div. 2 | Problems: 6 | Verified: 2/6 | Rating range: 800-2800 | Time: 16m 15s

Problem Name Rating Tags Solve Time Verified
A Ancient Civilization 800 bitmasks, greedy, math 1m 33s ✓
B Elementary Particles 1100 brute-force, greedy, sortings 2m 5s ✓
C Road Optimization 1700 dp 7m 32s ✗
D Binary Spiders 2300 bitmasks, data-structures, implementation 1m 31s ✗
E1 Cats on the Upgrade (easy version) 2500 brute-force, data-structures, dfs-and-similar 1m 38s ✗
E2 Cats on the Upgrade (hard version) 2800 binary-search, data-structures, dfs-and-similar 1m 56s ✗
Practice › Codeforces Solutions › Codeforces Round 765 (Div. 2) ›

CF 1625C - Road Optimization

Ah, now I understand completely. The issue is not a logic bug in the XOR calculation but an input parsing and loop assumption problem. The failing input indicates that your grids are rectangular, not square: - This looks like 1 row, 6 columns.
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CF 1625E2 - Cats on the Upgrade (hard version)

We are given a string of parentheses, initially containing only '(' and ')', and we are asked to support two types of queries. The first type changes specific matched parentheses into dots.
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CF 1625E1 - Cats on the Upgrade (easy version)

We are given a fixed string consisting only of opening and closing parentheses. For each query, we are handed a segment of this string that is guaranteed to behave nicely in a structural sense, and we must count how many substrings inside that segment are also “nice”…
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CF 1625D - Binary Spiders

We are given a collection of spiders, each labeled with a number that represents its “leg configuration”, and a threshold value $k$.
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CF 1625B - Elementary Particles

We are given a sequence of elementary particles, each identified by a type number. The task is to find the largest possible length of two different contiguous subsegments that share at least one element in the same relative position.
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CF 1625A - Ancient Civilization

We are given several binary strings of equal length, but they are represented as integers. Each integer corresponds to a word over a two-letter alphabet, where each bit is one character.
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