The 14th Huazhong Agricultural University Programming Contest

13 problems from The 14th Huazhong Agricultural University Programming Contest (contest 105838), difficulty -. 13/13 solutions verified against sample I/O.

13 items

The 14th Huazhong Agricultural University Programming Contest

Special | 13 problems | 13/13 verified | Difficulty - | 12m 58s

# Problem Rating Tags Accepted Time ✓
A A New Journey 1m 24s ✓
B Lunch! 43s ✓
C Cowardly Lizard IV 55s ✓
D Cowardly Lizard V 1m 5s ✓
E Creative Boki-chan 52s ✓
F Boki-chan Who Dislikes Mathematics 1m 6s ✓
G Who Likes Mathematics is not Boki-chan 47s ✓
H Defense Deployment 46s ✓
I We Must Be Together No Matter How Far 1m 7s ✓
J Skill Tree 52s ✓
K ruskal's Reconstruction Number 46s ✓
L Greedy World 1m 4s ✓
M Dye Your Color 1m 31s ✓
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CF 105838C - Cowardly Lizard IV

We are given an array of positive integers and many range queries. For each query, a segment from index $l$ to $r$ is chosen. Inside this segment, we are allowed to pick a split point $k$ such that $l le k < r$.
codeforces competitive-programming Jun 22, 2026
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CF 105838M - Dye Your Color

We are given a tree with $n$ nodes. Each node represents a region, and each region has a value that depends on whether it is currently marked as colored or not. Initially all nodes are uncolored and each node $i$ has a base value $ai$.
codeforces competitive-programming Jun 22, 2026
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CF 105838K - ruskal's Reconstruction Number

We are given a positive integer written as a decimal string. In one move, we are allowed to choose a single pair of adjacent digits and swap them. We may perform at most one such swap, or choose to do nothing.
codeforces competitive-programming Jun 22, 2026
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CF 105838I - We Must Be Together No Matter How Far

We are given a connected undirected graph with $n$ islands and exactly $n$ roads. Every road has cost 1, and the same road can be traversed multiple times, paying its cost each time.
codeforces competitive-programming Jun 22, 2026
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CF 105838J - Skill Tree

We are given a rooted tree where node 1 is the root. Each node represents a skill, and each skill has a value called its power.
codeforces competitive-programming Jun 22, 2026
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CF 105838G - Who Likes Mathematics is not Boki-chan

We are given a very large interval of integers, from $L$ to $R$, where $R$ can be as large as $10^{18}$. The task is to count how many numbers inside this interval satisfy a digit-based property: when you look at the decimal representation of a number, the absolute difference…
codeforces competitive-programming Jun 22, 2026
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CF 105838F - Boki-chan Who Dislikes Mathematics

We are working on a grid of all pairs $(i, j)$ where $1 le i le n$ and $1 le j le m$. For each pair, we look at the greatest common divisor of $i$ and $j$. From that gcd value $g$, we compute the number of divisors of $g$, written as $d(g)$.
codeforces competitive-programming Jun 22, 2026
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CF 105838E - Creative Boki-chan

We are given a sequence $b$ whose length is $n$. This sequence was originally produced from an unknown integer array $a$, but during the process, the array was modified in a structured way. The hidden construction is the following.
codeforces competitive-programming Jun 22, 2026
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CF 105838D - Cowardly Lizard V

We are given several independent test cases. In each test case, there are $n$ caves labeled from 1 to $n$, and a sequence of $n$ planned inspections, where each inspection targets one cave. The sequence is fixed and known in advance.
codeforces competitive-programming Jun 22, 2026
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CF 105838B - Lunch!

We are given a sequence of exactly three integers. We are allowed to rearrange these three values using swaps between any two positions, and after doing so we want the resulting arrangement to satisfy a very specific pattern: the first element must be strictly greater than the…
codeforces competitive-programming Jun 22, 2026
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CF 105838L - Greedy World

We start with a multiset of exactly $k$ numbers. Out of these, $k-1$ copies are equal to some value $x$, and a single element equals $y$. So initially the structure is extremely uniform except for one “disturbance”.
codeforces competitive-programming Jun 21, 2026
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CF 105838H - Defense Deployment

We are given multiple independent test cases. Each test case describes a set of points on an infinite 2D grid. Every point represents a tower placed at integer coordinates.
codeforces competitive-programming Jun 21, 2026
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CF 105838A - A New Journey

Each test case describes a group of candidates being evaluated on two independent dimensions: performance in a series of training contests, and performance in a problem-solving assessment outside contests.
codeforces competitive-programming Jun 21, 2026