Codeforces Round 856 (Div. 2)

Solutions for Codeforces Round 856 (Div. 2) (contest 1794). 3/5 problems verified against sample I/O. Difficulty range: 800-2400.

5 items

Codeforces Round 856 (Div. 2)

Type: Div. 2 | Problems: 5 | Verified: 3/5 | Rating range: 800-2400 | Time: 10m 23s

Problem	Name	Rating	Tags	Solve Time	Verified
A	Prefix and Suffix Array	800	strings	1m 33s	✓
B	Not Dividing	900	constructive-algorithms, greedy, math	2m 22s	✗
C	Scoring Subsequences	1300	binary-search, greedy, math	53s	✗
D	Counting Factorizations	1900	combinatorics, divide-and-conquer, dp	2m 26s	✓
E	Labeling the Tree with Distances	2400	data-structures, dp, greedy	3m 9s	✓

Practice › Codeforces Solutions › Codeforces Round 856 (Div. 2) ›

CF 1794E - Labeling the Tree with Distances

We are given a tree with $n$ vertices and a multiset of $n-1$ integers. One vertex is special: it is not assigned any value from the list, while every other vertex must be assigned exactly one number from the list.

Practice › Codeforces Solutions › Codeforces Round 856 (Div. 2) ›

CF 1794D - Counting Factorizations

We are given a multiset of $2n$ integers, which may include both primes and positive integers greater than one. The goal is to count how many positive integers $m$ have a prime factorization that produces exactly this multiset when each prime and its exponent are included as…

Practice › Codeforces Solutions › Codeforces Round 856 (Div. 2) ›

CF 1794B - Not Dividing

We are given an array of positive integers. The goal is to modify the array so that no element divides the next element, using only increments of 1. Each element can be incremented multiple times, but the total number of operations must not exceed twice the array length.

Practice › Codeforces Solutions › Codeforces Round 856 (Div. 2) ›

CF 1794A - Prefix and Suffix Array

We are given a hidden string $s$ of length $n$. Instead of seeing $s$ directly, we are shown a multiset of strings consisting of every non-empty prefix of $s$ and every non-empty suffix of $s$, except for $s$ itself.

Practice › Codeforces Solutions › Codeforces Round 856 (Div. 2) ›

CF 1794C - Scoring Subsequences

We are given a non-decreasing array. For every prefix a[1...k], we must determine a special value called the cost. For any subsequence of length d, its score is the product of its elements divided by d!.