The 2021 ICPC Asia Macau Regional Contest

11 problems from The 2021 ICPC Asia Macau Regional Contest (contest 104373), difficulty -. 11/11 solutions verified against sample I/O.

11 items

The 2021 ICPC Asia Macau Regional Contest

ICPC/IOI | 11 problems | 11/11 verified | Difficulty - | 11m 1s

# Problem Rating Tags Accepted Time ✓
A So I'll Max Out My Constructive Algorithm Skills 59s ✓
B The Matching System 1m 4s ✓
C Laser Trap 57s ✓
D Shortest Path Fast Algorithm 1m 17s ✓
E Pass the Ball! 58s ✓
F Sandpile on Clique 55s ✓
G Cyclic Buffer 52s ✓
H Permutation on Tree 53s ✓
I LCS Spanning Tree 1m 8s ✓
J Colorful Tree 56s ✓
K Link-Cut Tree 1m 2s ✓
Practice › Codeforces Solutions › The 2021 ICPC Asia Macau Regional Contest ›

CF 104373K - Link-Cut Tree

We are given an undirected graph where each edge has a very special weight: the i-th edge in input order has weight $2^i$.
codeforces competitive-programming Jul 1, 2026
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CF 104373J - Colorful Tree

We are building a tree incrementally. The structure starts with a single node, and each operation either attaches a new node to an existing node with a weighted edge or changes the color of an existing node.
codeforces competitive-programming Jul 1, 2026
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CF 104373I - LCS Spanning Tree

We are given a collection of strings, each representing a vertex in a complete undirected graph. Every pair of vertices is connected, and the weight of an edge is defined by how similar the two strings are: specifically, it is the length of the longest substring that appears…
codeforces competitive-programming Jul 1, 2026
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CF 104373H - Permutation on Tree

We are given a rooted tree with $n$ labeled vertices. We consider all permutations of the vertices, but we only keep those permutations that respect the tree’s ancestor structure: whenever a node $u$ is an ancestor of node $v$, then $u$ must appear earlier in the permutation.
codeforces competitive-programming Jul 1, 2026
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CF 104373G - Cyclic Buffer

We are given a circular array that contains a permutation of the numbers from 1 to n. There is a fixed window of size k that represents the “visible” part of the buffer, specifically the first k positions at any moment.
codeforces competitive-programming Jul 1, 2026
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CF 104373D - Shortest Path Fast Algorithm

The algorithm in the statement is a modified shortest path routine that behaves like SPFA but uses a priority queue instead of a FIFO queue. Every time a vertex is extracted from the queue, it relaxes its outgoing edges.
codeforces competitive-programming Jul 1, 2026
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CF 104373F - Sandpile on Clique

We are given a complete graph with $n$ vertices, where every vertex is connected to every other vertex. Each vertex starts with some number of chips.
codeforces competitive-programming Jul 1, 2026
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CF 104373E - Pass the Ball!

We are given a directed mapping over n children. Each child always passes whatever ball they currently hold to exactly one fixed destination child p[i].
codeforces competitive-programming Jul 1, 2026
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CF 104373B - The Matching System

We are given a length $n$, and we must construct two binary strings of that length: a pattern string and a target string. The pattern is not purely binary; it also contains two special symbols that define a recursive matching process against the binary string.
codeforces competitive-programming Jul 1, 2026
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CF 104373A - So I'll Max Out My Constructive Algorithm Skills

We are given a square grid of size $n times n$, where every cell contains a distinct integer from 1 to $n^2$. You can think of this grid as a weighted graph laid out on a lattice: each cell is a node, and edges exist between orthogonally adjacent cells.
codeforces competitive-programming Jul 1, 2026
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CF 104373C - Laser Trap

We are given a set of points in the plane. Each point acts as a laser generator, and every pair of generators is connected by a straight laser segment. So for n points, the system forms a complete geometric graph where every edge is a segment between two given coordinates.
codeforces competitive-programming Jul 1, 2026