NCTU PCCA Winter Contest 2021

8 problems from NCTU PCCA Winter Contest 2021 (contest 102946), difficulty -. 6/8 solutions verified against sample I/O.

8 items

NCTU PCCA Winter Contest 2021

Special | 8 problems | 6/8 verified | Difficulty - | 10m 4s

# Problem Rating Tags Accepted Time ✓
A A Water Problem 45s ✓
B Bongcloud 50s ✓
C Chicken Nuggets 2m 32s
D Discombobulator 3000 57s ✓
E Evenly Distributed 1m 4s ✓
F Fishy Study 50s ✓
G Group-Theoretic Machine 41s ✓
H Halting Problem 2m 25s
Practice › Codeforces Solutions › NCTU PCCA Winter Contest 2021 ›

CF 102946H - Halting Problem

Let the $2times 2times 3$ torus be the Cartesian product $$T = mathbb{Z}2 times mathbb{Z}2 times mathbb{Z}3,$$ so each element is a triple $(x,y,z)$ with $x,y in {0,1}$ and $z in {0,1,2}$, with arithmetic taken modulo $2,2,3$ respectively. This gives $12$ vertices.
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CF 102946G - Group-Theoretic Machine

We are given six sensors in 3D space, each tied to a specific cube face color. In a valid configuration, these sensors must each touch one face of a solid cube of side length d. The cube itself is not axis-aligned, so we are free to rotate and translate it arbitrarily in space.
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CF 102946F - Fishy Study

We are working with a very small square grid, at most eight by eight, where each cell either contains a fish or is empty. Alongside this grid there is a special token, the sea urchin, which occupies exactly one cell and moves every day to a neighboring cell that shares an edge.
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CF 102946C - Chicken Nuggets

Let the $2times 2times 3$ torus be the Cartesian product $$T = mathbb{Z}2 times mathbb{Z}2 times mathbb{Z}3,$$ so each element is a triple $(x,y,z)$ with $x,y in {0,1}$ and $z in {0,1,2}$, with arithmetic taken modulo $2,2,3$ respectively. This gives $12$ vertices.
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CF 102946E - Evenly Distributed

We are asked to distribute a total of k fish into n fish tanks, where each tank must contain a positive integer number of fish.
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CF 102946D - Discombobulator 3000

We are given two hidden permutations, both containing the numbers from 1 to n exactly once. One permutation is a cyclic rotation of the other, but we do not know either of them and we also do not know the rotation amount k.
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CF 102946B - Bongcloud

We are given a grid of size $n times m$ where each cell is either 0 or 1. From this grid, we consider every possible subrectangle aligned with the grid lines.
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CF 102946A - A Water Problem

We are given a list of integers representing water volumes in several fish tanks. For each tank, we need to compute a value based on two parts of the number: the number itself and the sum of its digits.
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