2021 ICPC Universidad Nacional de Colombia Programming Contest

13 problems from 2021 ICPC Universidad Nacional de Colombia Programming Contest (contest 103577), difficulty -. 13/13 solutions verified against sample I/O.

13 items

2021 ICPC Universidad Nacional de Colombia Programming Contest

ICPC/IOI | 13 problems | 13/13 verified | Difficulty - | 31m 25s

# Problem Rating Tags Accepted Time ✓
A Artistic Swimming 2m 27s ✓
B Blockchain 43s ✓
C Corona 2m 28s ✓
D Derivative of polynomial 53s ✓
E Molecules 1m 7s ✓
F Flow of binary matrix 49s ✓
G Matematical Transformation 17m 34s ✓
H Hiking trip 52s ✓
I Impossible problems 49s ✓
J Just enough squares 1m 6s ✓
K Walking Tiles 50s ✓
L Convert to heap 1m ✓
M Classroom Reordering 47s ✓
Practice › Codeforces Solutions › 2021 ICPC Universidad Nacional de Colombia Programming Contest ›

CF 103577G - Matematical Transformation

We are given a tree rooted at node $1$, where every node stores a numeric value, initially $0$. Two types of operations are performed online. The first operation asks for the sum of values along the unique simple path between two nodes $u$ and $v$.
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CF 103577L - Convert to heap

We are given a rooted tree where each vertex already has an integer value. The root is node 1. Alongside the tree, we are given a list of update values. Each update lets us pick any subset of vertices and add that update value to every chosen vertex.
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CF 103577M - Classroom Reordering

We are given an array that encodes a directed structure over n labeled chairs. Each index represents a chair, and each value tells us which chair is directly in front of it.
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CF 103577K - Walking Tiles

We are given two sets of points on an infinite 2D integer grid. One set contains “loose tiles” and the other contains “fixed tiles”.
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CF 103577J - Just enough squares

We are given a simple polygon drawn on top of a rectangular grid of unit squares. Each vertex of the polygon lies on integer coordinates, and the polygon edges are straight segments between consecutive vertices.
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CF 103577I - Impossible problems

We are given a set of $n$ problem setters and $n$ topics. Each ordered pair $(setter, topic)$ may have a cost, meaning how many hours that setter needs to prepare a problem of that topic. Only some of these pairs are available, given as $m$ entries.
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CF 103577H - Hiking trip

Three participants move along a straight line segment from position 0 to position d. Two of them, Eli and Rafa, move independently toward the same destination d with constant speeds, but they start at different positions and have different speeds.
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CF 103577F - Flow of binary matrix

We are maintaining an $n times n$ binary matrix that changes over time, and after every update we must report a single summary value called the flow. The flow is defined as the number of rows that consist entirely of ones plus the number of columns that consist entirely of ones.
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CF 103577E - Molecules

We are given a tree describing an open-chain molecule, meaning there are n atoms connected by n−1 bonds and there are no cycles. The task is to output a permutation of all atoms. For any such permutation, consider a fixed atom u.
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CF 103577C - Corona

Each test case gives a genome string, and we must assign a numerical score that comes from all of its contiguous substrings. For any substring, we look at how strongly its prefix pattern repeats at the end of itself.
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CF 103577A - Artistic Swimming

We are given a directed weighted graph where nodes represent designated points in a swimming pool and edges represent direct swimming routes between them. Each edge has a travel time.
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CF 103577D - Derivative of polynomial

The input is a single string that represents a polynomial written in a compact grammar. Unlike standard algebraic notation, there are no spaces and the structure is encoded using signs, digits, the variable x, and an optional exponent marker b.
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CF 103577B - Blockchain

We are given one or more undirected multigraphs. Each edge connects two vertices and carries a positive integer weight.
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