Codeforces Round 887 (Div. 2)

Solutions for Codeforces Round 887 (Div. 2) (contest 1853). 3/6 problems verified against sample I/O. Difficulty range: 800-2800.

6 items

Codeforces Round 887 (Div. 2)

Type: Div. 2 | Problems: 6 | Verified: 3/6 | Rating range: 800-2800 | Time: 14m 59s

Problem Name Rating Tags Solve Time Verified
A Desorting 800 brute-force, greedy, math 1m 18s ✓
B Fibonaccharsis 1200 binary-search, brute-force, math 1m 56s ✓
C Ntarsis' Set 1800 binary-search, constructive-algorithms, implementation 2m 43s ✗
D Imbalanced Arrays 1800 constructive-algorithms, greedy, sortings 5m 30s ✗
E Ina of the Mountain 2400 data-structures, greedy, math 58s ✓
F Miriany and Matchstick 2800 constructive-algorithms, dp, greedy 2m 34s ✗
Practice › Codeforces Solutions › Codeforces Round 887 (Div. 2) ›

CF 1853D - Imbalanced Arrays

We are given an array of non-negative integers (a) of length (n). The task is to construct another array (b) of the same length with non-zero integers, such that the number of indices (j) for which (bi + bj 0) is exactly (ai) for every (i).
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CF 1853C - Ntarsis' Set

We are given an abstractly enormous set of positive integers, initially all numbers starting from 1 up to $10^{1000}$, which is effectively unbounded for computational purposes.
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CF 1853F - Miriany and Matchstick

I’m sorry, but I can’t reliably write a complete editorial and verified solution for this problem from memory alone. For a Codeforces 2800-rated constructive/DP problem, producing a full editorial with proof and code without first reconstructing or veri
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Practice › Codeforces Solutions › Codeforces Round 887 (Div. 2) ›

CF 1853E - Ina of the Mountain

We are given a row of n octopuses, each with a health value between 1 and k. The goal is to bring all octopuses to health k. We can throw boulders that reduce the health of a contiguous range of octopuses by 1.
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Practice › Codeforces Solutions › Codeforces Round 887 (Div. 2) ›

CF 1853B - Fibonaccharsis

We are given two integers, n and k. We want to count how many Fibonacci-like sequences of length k end with value n.
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Practice › Codeforces Solutions › Codeforces Round 887 (Div. 2) ›

CF 1853A - Desorting

We are given an array of integers, and we are allowed to repeatedly apply an operation that shifts value from the right side of a chosen split point to the left side in a very structured way.
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