The 2025 Homs Collegiate programming contest

13 problems from The 2025 Homs Collegiate programming contest (contest 106016), difficulty -. 13/13 solutions verified against sample I/O.

13 items

The 2025 Homs Collegiate programming contest

Special | 13 problems | 13/13 verified | Difficulty - | 14m 17s

#	Problem	Time	✓
A	The Beauty Of Homs	53s	✓
B	Colored Tree	1m 4s	✓
C	USD vs Liras	55s	✓
D	Least Uncommon Divisor	1m 12s	✓
E	a less than b	1m 6s	✓
F	Split	1m 1s	✓
G	Mexy Permutation	54s	✓
H	Median Gcd	1m 33s	✓
I	W/S TREE	1m 13s	✓
J	Arranged Marriage	56s	✓
K	Cookies	1m 5s	✓
L	Good Sets	55s	✓
M	Random Spanning Tree	1m 30s	✓

Practice › Codeforces Solutions › The 2025 Homs Collegiate programming contest ›

CF 106016M - Random Spanning Tree

We are working with labeled trees on vertices from 1 to n. Among all spanning trees, we only keep those in which the unique path between vertex 1 and vertex n is a diameter of the tree, meaning no other pair of vertices is farther apart than 1 and n are.

Practice › Codeforces Solutions › The 2025 Homs Collegiate programming contest ›

CF 106016J - Arranged Marriage

We are given a sequence of families, each family contributing a number of boys and a number of girls. For any contiguous segment of families, we gather all boys and girls from those families.

Practice › Codeforces Solutions › The 2025 Homs Collegiate programming contest ›

CF 106016H - Median Gcd

We start with every integer from l to r placed on a board. At each step we look at all remaining numbers, compute their greatest common divisor, add it to a running score, then delete the median element of the current set.

Practice › Codeforces Solutions › The 2025 Homs Collegiate programming contest ›

CF 106016G - Mexy Permutation

We are asked to construct a permutation of numbers from 1 to n such that a derived array, formed from adjacent differences, avoids having many small positive integers.

Practice › Codeforces Solutions › The 2025 Homs Collegiate programming contest ›

CF 106016F - Split

We are given an array of non-negative integers. The task is to split the elements into two non-empty groups such that every element belongs to exactly one group.

Practice › Codeforces Solutions › The 2025 Homs Collegiate programming contest ›

CF 106016D - Least Uncommon Divisor

We are given a fixed number $x$ and a long list of values $ai$. For each $ai$, we want to find the smallest positive integer $z$ that satisfies two conditions: it must divide $x$, and it must fail to divide $ai$.

Practice › Codeforces Solutions › The 2025 Homs Collegiate programming contest ›

CF 106016B - Colored Tree

We are given a tree where each vertex initially carries a color label. Then those labels are randomly permuted and reassigned to the vertices, so the multiset of colors stays the same but their locations become uniformly random.

Practice › Codeforces Solutions › The 2025 Homs Collegiate programming contest ›

CF 106016A - The Beauty Of Homs

The input describes a single prompt that is always the same idea, a request to “tell a joke”. There is no hidden structure inside it that affects the answer, and no computation is required on the text.

Practice › Codeforces Solutions › The 2025 Homs Collegiate programming contest ›

CF 106016K - Cookies

A line of children is given, each child carrying a rating. We must assign a positive number of cookies to every child, but the assignment cannot be arbitrary.

Practice › Codeforces Solutions › The 2025 Homs Collegiate programming contest ›

CF 106016L - Good Sets

We are given an array where each position has a value, and we want to form special subsets of indices. The key restriction is that any two chosen indices must be separated by at least one unused position, so we can never pick adjacent indices.

Practice › Codeforces Solutions › The 2025 Homs Collegiate programming contest ›

CF 106016I - W/S TREE

We are given a tree where each node carries a numeric value, which can be positive or negative. We start from node 1 and walk along edges, collecting the value of a node the first time we visit it.

Practice › Codeforces Solutions › The 2025 Homs Collegiate programming contest ›

CF 106016E - a less than b

We are given two strings of equal length, and we are allowed to modify the first string using at most one operation. That operation picks a contiguous segment and reverses it.

Practice › Codeforces Solutions › The 2025 Homs Collegiate programming contest ›

CF 106016C - USD vs Liras

Each day Omar must settle a demand that is expressed in two currencies. For day i, there is a required amount of dollars ai and a conversion rate bi that tells how expensive it is to replace one dollar using liras. On that day Omar can split the payment in two parts.