Codeforces Round 1003 (Div. 4)

9 problems from Codeforces Round 1003 (Div. 4) (contest 2065), difficulty 800-2200. 5/9 solutions verified against sample I/O.

9 items

Codeforces Round 1003 (Div. 4)

Div. 4 | 9 problems | 5/9 verified | Difficulty 800-2200 | 16m 33s

# Problem Rating Tags Accepted Time ✓
A Skibidus and Amog'u 800 brute-force, constructive-algorithms, greedy 55,608 4m 36s
B Skibidus and Ohio 800 strings 42,052 1m 37s ✓
C1 Skibidus and Fanum Tax (easy version) 1100 binary-search, dp, greedy 27,751 1m 17s ✓
C2 Skibidus and Fanum Tax (hard version) 1300 binary-search, greedy 18,788 1m 25s ✓
D Skibidus and Sigma 1200 greedy, sortings 20,621 1m 21s ✓
E Skibidus and Rizz 1600 constructive-algorithms, greedy, strings 11,964 1m 29s
F Skibidus and Slay 1700 data-structures, dfs-and-similar, graphs 7,088 1m 13s ✓
G Skibidus and Capping 1700 combinatorics, math, number-theory 6,278 1m 44s
H Bro Thinks He's Him 2200 combinatorics, data-structures, divide-and-conquer 1,970 1m 51s
Practice › Codeforces Solutions › Codeforces Round 1003 (Div. 4) ›

CF 2065H - Bro Thinks He's Him

The problem asks us to work with a binary string and queries that flip individual bits. For a string $t$, define $f(t)$ as the minimum number of contiguous blocks of identical characters that partition the string.
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CF 2065G - Skibidus and Capping

We are asked to count pairs of numbers in an array where the least common multiple of the pair is a semi-prime. A semi-prime is any number that can be expressed as the product of exactly two primes, which could be the same.
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CF 2065A - Skibidus and Amog'u

We are given a word that is already in its singular form in a very constrained toy language. Every word is constructed from a root string, and the singular form is always created by appending the suffix “us” to that root.
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CF 2065E - Skibidus and Rizz

The task asks us to construct a binary string of a specified length containing a fixed number of 0s and 1s such that the maximum difference between the counts of 0s and 1s in any substring is exactly k.
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CF 2065F - Skibidus and Slay

The problem asks us to analyze a tree where each vertex has a number assigned to it, and for every number from 1 to n, we must decide if there exists a simple path in the tree where that number is the majority.
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CF 2065D - Skibidus and Sigma

We are given multiple arrays of equal length, and we want to merge them in some order to maximize a special score. The score of a single array is computed by summing all its prefix sums. For example, if an array is [a, b, c], its score is a + (a+b) + (a+b+c) = 3a + 2b + c.
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CF 2065C2 - Skibidus and Fanum Tax (hard version)

We are given an array a and another array b. For every position in a, we have a binary-like choice: we can either leave a[i] unchanged or replace it with a transformed value obtained by picking some element b[j] and computing b[j] - a[i].
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CF 2065B - Skibidus and Ohio

We are given a string composed of lowercase letters. Skibidus can repeatedly perform an operation on any pair of consecutive identical letters: he replaces the first letter with any letter and deletes the second.
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CF 2065C1 - Skibidus and Fanum Tax (easy version)

We are given an array where each position initially contains a fixed value. For every position, we are allowed one optional transformation: we can replace the value at that position with the result of subtracting it from a single fixed number.
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