Codeforces Round 884 (Div. 1 + Div. 2)

Solutions for Codeforces Round 884 (Div. 1 + Div. 2) (contest 1844). 1/9 problems verified against sample I/O. Difficulty range: 800-3400.

9 items

Codeforces Round 884 (Div. 1 + Div. 2)

Type: Div. 1+2 | Problems: 9 | Verified: 1/9 | Rating range: 800-3400 | Time: 17m 33s

Problem	Name	Rating	Tags	Solve Time	Verified
A	Subtraction Game	800	constructive-algorithms, games	1m 46s	✗
B	Permutations & Primes	1000	constructive-algorithms, math	1m 21s	✗
C	Particles	1300	dp, greedy, implementation	5m 10s	✗
D	Row Major	1400	constructive-algorithms, greedy, math	1m 44s	✓
E	Great Grids	2400	2-sat, constructive-algorithms, dfs-and-similar	1m 39s	✗
F1	Min Cost Permutation (Easy Version)	2600	brute-force, constructive-algorithms, greedy	1m 17s	✗
F2	Min Cost Permutation (Hard Version)	2800	binary-search, constructive-algorithms, data-structures	1m 29s	✗
G	Tree Weights	3000	bitmasks, constructive-algorithms, data-structures	1m 28s	✗
H	Multiple of Three Cycles	3400	combinatorics, data-structures, dp	1m 39s	✗

Practice › Codeforces Solutions › Codeforces Round 884 (Div. 1 + Div. 2) ›

CF 1844H - Multiple of Three Cycles

We are asked to process a sequence of updates on an initially empty array of length $n$. Each update sets a single position in the array to a number, and after all updates, the array becomes a permutation of $1$ through $n$.

Practice › Codeforces Solutions › Codeforces Round 884 (Div. 1 + Div. 2) ›

CF 1844G - Tree Weights

We are given a tree with n nodes and n-1 edges, where the edges are unlabeled with weights. Instead, we are provided with the sum of weights along the paths between consecutive nodes from 1 to n.

Practice › Codeforces Solutions › Codeforces Round 884 (Div. 1 + Div. 2) ›

CF 1844C - Particles

We are given a sequence of particles arranged in a line, each with an integer charge. We have a device that allows us to remove any particle, after which the two neighboring particles merge into one particle whose charge is the sum of the two neighbors.

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CF 1844F2 - Min Cost Permutation (Hard Version)

We are given an array of positive integers and an integer $c$, which can be negative. The task is to reorder the array into a permutation that minimizes the sum of absolute differences $ In practical terms, we are aligning the differences between consecutive elements to match…

Practice › Codeforces Solutions › Codeforces Round 884 (Div. 1 + Div. 2) ›

CF 1844F1 - Min Cost Permutation (Easy Version)

We are given an array of positive integers and a number $c$ that can be negative, zero, or positive. The task is to reorder the array into a permutation that minimizes the sum of absolute differences between consecutive elements, adjusted by $c$.

Practice › Codeforces Solutions › Codeforces Round 884 (Div. 1 + Div. 2) ›

CF 1844E - Great Grids

We are working with an $n times m$ grid where every cell must be assigned one of three symbols: $A$, $B$, or $C$. The grid is not arbitrary, because two structural rules constrain it heavily.

Practice › Codeforces Solutions › Codeforces Round 884 (Div. 1 + Div. 2) ›

CF 1844D - Row Major

We need to construct a string of length n using as few distinct lowercase letters as possible. The catch is that the string must remain valid for every possible grid shape whose row-major traversal produces that string.

Practice › Codeforces Solutions › Codeforces Round 884 (Div. 1 + Div. 2) ›

CF 1844A - Subtraction Game

We are given two move sizes, $a$ and $b$, with $a < b$. Two players play a subtraction game starting from a pile of $n$ stones. On each turn, a player must remove exactly $a$ or exactly $b$ stones. A player who cannot make a valid move loses immediately.

Practice › Codeforces Solutions › Codeforces Round 884 (Div. 1 + Div. 2) ›

CF 1844B - Permutations & Primes

We are asked to construct a permutation of the integers from 1 to $n$ such that a particular metric, which we call "primality," is maximized. Primality is defined as the number of contiguous subarrays whose minimum excluded number (MEX) is a prime.