The 2019 ICPC Asia Yinchuan Regional Contest

14 problems from The 2019 ICPC Asia Yinchuan Regional Contest (contest 104021), difficulty -. 14/14 solutions verified against sample I/O.

14 items

The 2019 ICPC Asia Yinchuan Regional Contest

ICPC/IOI | 14 problems | 14/14 verified | Difficulty - | 11m 38s

# Problem Rating Tags Accepted Time ✓
A Girls Band Party 48s ✓
B So Easy 40s ✓
C Image Processing 53s ✓
D Easy Problem 59s ✓
E XOR Tree 53s ✓
F Function! 55s ✓
G Pot!! 58s ✓
H Delivery Route 45s ✓
I Base62 49s ✓
J Toad's Travel 1m 6s ✓
K Largest Common Submatrix 42s ✓
L Xian Xiang 58s ✓
M Crazy Cake 39s ✓
N Fibonacci Sequence 33s ✓
Practice › Codeforces Solutions › The 2019 ICPC Asia Yinchuan Regional Contest ›

CF 104021N - Fibonacci Sequence

The task is extremely direct: we are asked to generate the beginning of a well-known integer sequence defined purely by recurrence. The sequence starts with two fixed seeds, both equal to one, and every later value is obtained by summing the previous two values.
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CF 104021J - Toad's Travel

We are given a connected undirected weighted graph with a strong structural restriction: every edge belongs to at most one simple cycle. This makes the graph essentially a tree with a collection of disjoint cycles attached, i.e. a cactus graph.
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CF 104021L - Xian Xiang

We are given a small grid, up to 7 by 7, where some cells contain “objects” and others are empty. Each object is described by a short string of length at most 5, and each position in the string represents an attribute.
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CF 104021M - Crazy Cake

We place $n$ identical points evenly around a circle, and we are allowed to draw straight chords between any two of these points. The only restriction is geometric: no two chords are allowed to cross in their interiors.
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CF 104021K - Largest Common Submatrix

We are given two square grids of size $n times m$, each cell containing a unique integer within that grid. Values inside a single matrix never repeat, but across the two matrices, values may appear in both.
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CF 104021I - Base62

We are given a number written in an arbitrary positional numeral system with base $x$, where digits are not limited to 0-9 but extend through uppercase and lowercase letters up to a total of 62 distinct symbols.
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CF 104021G - Pot!!

We are given an array of length up to one hundred thousand. Every element starts as 1, and then we perform a sequence of operations that either multiply a contiguous segment by a small integer between 2 and 10, or ask for a query over a segment.
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CF 104021H - Delivery Route

We are given a directed weighted graph with some bidirectional roads and some one-way roads. Each road has a cost, which can even be negative for some directed roads due to special infrastructure.
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CF 104021D - Easy Problem

We are asked to sum a weight over many sequences. Each sequence has fixed length n, and every element lies between 1 and m. We only consider sequences whose greatest common divisor is exactly d. For each valid sequence (a1, a2, ...
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CF 104021F - Function!

We are given a function family that is essentially linear scaling. For each parameter $a0$, the function maps a real number $x$ to $a cdot x$, and its inverse simply divides by $a$.
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CF 104021E - XOR Tree

We are working with a rooted tree where every node stores an integer value. For any node $x$, we look at a restricted region of the tree: all descendants of $x$ whose depth from $x$ is at most $k$. From these nodes we collect their values into a multiset $p(x, k)$.
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CF 104021C - Image Processing

We are given a sequence of images processed one by one from left to right. Each image has a hidden “true” contrast value, but what we are directly given is an encoded sequence.
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CF 104021A - Girls Band Party

We are given multiple independent scenarios. In each scenario we own a collection of cards, where every card has a name, a color, and a power value.
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CF 104021B - So Easy

We are given an initially zero matrix of size $n times n$. A sequence of operations has been applied where each operation chooses either a full row or a full column and adds a positive integer to every cell in that row or column.
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