Codeforces Round 689 (Div. 2, based on Zed Code Competition)

Solutions for Codeforces Round 689 (Div. 2, based on Zed Code Competition) (contest 1461). 2/6 problems verified against sample I/O. Difficulty range: 800-2700.

6 items

Codeforces Round 689 (Div. 2, based on Zed Code Competition)

Type: Div. 2 | Problems: 6 | Verified: 2/6 | Rating range: 800-2700 | Time: 19m 34s

Problem Name Rating Tags Solve Time Verified
A String Generation 800 constructive-algorithms, greedy 2m 11s ✗
B Find the Spruce 1400 brute-force, dp, implementation 3m 11s ✗
C Random Events 1500 dp, math, probabilities 7m 21s ✓
D Divide and Summarize 1600 binary-search, brute-force, data-structures 2m 6s ✓
E Water Level 2200 brute-force, graphs, greedy 2m 57s ✗
F Mathematical Expression 2700 constructive-algorithms, dp, greedy 1m 48s ✗
Practice › Codeforces Solutions › Codeforces Round 689 (Div. 2, based on Zed Code Competition) ›

CF 1461C - Random Events

We are given an initial permutation and a sequence of probabilistic operations. Each operation focuses on a prefix of the permutation and, independently, sorts that prefix with a given probability.
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Practice › Codeforces Solutions › Codeforces Round 689 (Div. 2, based on Zed Code Competition) ›

CF 1461E - Water Level

We are asked to manage a water cooler over a number of days. The cooler starts with k liters of water, and every day x liters are consumed by coworkers. At the beginning of each day, John can add exactly y liters of water if doing so does not exceed the maximum limit r.
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Practice › Codeforces Solutions › Codeforces Round 689 (Div. 2, based on Zed Code Competition) ›

CF 1461F - Mathematical Expression

We are given a sequence of digits, each between 0 and 9, and a set of allowed operators, which can be any combination of addition, subtraction, and multiplication.
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CF 1461D - Divide and Summarize

We start with an array and repeatedly apply a very specific splitting rule. For any current array, compute $$mid = leftlfloor frac{min + max}{2} rightrfloor$$ All elements whose value is at most mid form one group, and all elements whose value is greater than mid form the other.
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Practice › Codeforces Solutions › Codeforces Round 689 (Div. 2, based on Zed Code Competition) ›

CF 1461B - Find the Spruce

We are given a grid made of two types of cells: filled cells marked with and empty cells marked with .. Inside this grid, we want to count how many valid “spruce shapes” exist.
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Practice › Codeforces Solutions › Codeforces Round 689 (Div. 2, based on Zed Code Competition) ›

CF 1461A - String Generation

We are asked to construct a string of length n using only the characters 'a', 'b', and 'c', while ensuring that no palindromic substring exceeds length k. A substring is any contiguous segment of the string, and a palindrome reads the same forwards and backwards.
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