Codeforces Round 816 (Div. 2)

Solutions for Codeforces Round 816 (Div. 2) (contest 1715). 2/6 problems verified against sample I/O. Difficulty range: 800-2700.

6 items

Codeforces Round 816 (Div. 2)

Type: Div. 2 | Problems: 6 | Verified: 2/6 | Rating range: 800-2700 | Time: 17m 21s

Problem Name Rating Tags Solve Time Verified
A Crossmarket 800 constructive-algorithms, greedy, math 58s ✗
B Beautiful Array 1000 constructive-algorithms, greedy, math 2m 2s ✗
C Monoblock 1700 combinatorics, data-structures, implementation 2m 9s ✓
D 2+ doors 1900 2-sat, bitmasks, graphs 2m 40s ✗
E Long Way Home 2400 data-structures, divide-and-conquer, dp 7m 33s ✓
F Crop Squares 2700 constructive-algorithms, geometry, interactive 1m 59s ✗
Practice › Codeforces Solutions › Codeforces Round 816 (Div. 2) ›

CF 1715E - Long Way Home

Stanley wants to travel from city 1 to every other city in a country with two types of transport: roads and flights. The roads are given explicitly as edges with weights, forming an undirected graph.
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CF 1715F - Crop Squares

We are given a rectangular field aligned with axes, and somewhere inside it there is a hidden axis-aligned unit square whose lower-left corner is unknown. We cannot directly query points or coordinates.
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CF 1715D - 2+ doors

We are looking for an array of integers where every query describes the bitwise OR of two positions. A query (i, j, x) means that the value stored at position i OR the value stored at position j must equal x.
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CF 1715C - Monoblock

We are given an array of integers, and we define its awesomeness as the minimum number of consecutive identical blocks the array can be split into. For example, [1,1,2,2,2,3] has awesomeness 3 because it can be split into [1,1], [2,2,2], [3].
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CF 1715B - Beautiful Array

We are asked to construct an array of length n consisting of non-negative integers. Two global constraints must be satisfied at the same time. First, the sum of all elements must be exactly s.
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CF 1715A - Crossmarket

The store is an n × m grid. Stanley starts in the upper-left corner and wants to reach the lower-right corner. Megan starts in the lower-left corner and wants to reach the upper-right corner. Moving to a neighboring cell costs one unit of energy.
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