The 2021 ICPC Asia Shanghai Regional Programming Contest

13 problems from The 2021 ICPC Asia Shanghai Regional Programming Contest (contest 103446), difficulty -. 13/13 solutions verified against sample I/O.

13 items

The 2021 ICPC Asia Shanghai Regional Programming Contest

ICPC/IOI | 13 problems | 13/13 verified | Difficulty - | 11m 12s

# Problem Rating Tags Accepted Time ✓
A Strange Functions 1m 3s ✓
B Strange Permutations 43s ✓
C Strange Matrices 1m 8s ✓
D Strange Fractions 37s ✓
E Strange Integers 38s ✓
F Kaiji! 1m 2s ✓
G Edge Groups 1m 15s ✓
H Life is a Game 47s ✓
I Steadily Growing Steam 49s ✓
J Two Binary Strings Problem 52s ✓
K Circle of Life 42s ✓
L Three,Three,Three 46s ✓
M Harmony in Harmony 50s ✓
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CF 103446M - Harmony in Harmony

We are given a unit area region that is split twice into n equal-area pieces. The first split produces regions S1 through Sn, each of area 1/n. The second split produces regions A1 through An, also each of area 1/n.
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CF 103446L - Three,Three,Three

We are given a graph where every vertex has degree exactly three. The graph may contain self-loops or multiple edges, so edges are not guaranteed to be simple, but each vertex still has exactly three incident edge occurrences.
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CF 103446J - Two Binary Strings Problem

We are given two binary strings of equal length. One string, call it A, represents an array of 0s and 1s. The second string B describes a target condition that must be matched at every position under a sliding window interpretation.
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CF 103446K - Circle of Life

We are working with a line of $n$ vertices arranged from left to right, where each adjacent pair is connected, forming a simple path. A configuration is a binary string of length $n$, where a 1 means a Twinkle exists at that vertex and 0 means it is empty.
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CF 103446I - Steadily Growing Steam

We are given a small collection of cards, each card carrying two independent attributes: a point value used for balancing and a profit value used for scoring. The game is a two-phase interaction between Alice and Bob.
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CF 103446H - Life is a Game

We are given a connected undirected graph where each city has a one-time reward value, and each road has a minimum required “ability” needed to traverse it. A player starts at a chosen city with an initial ability value.
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CF 103446G - Edge Groups

We are given a connected undirected graph with n vertices and exactly n − 1 edges, so the structure is a tree. The number of vertices is odd, which implies the number of edges is even, since a tree always has n − 1 edges.
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CF 103446F - Kaiji!

We are given a large multiset of integers generated by a recurrence. Conceptually, think of it as a box containing many balls, each labeled with a value.
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CF 103446B - Strange Permutations

We are given a permutation $P$ of the numbers from $1$ to $n$. We want to count how many permutations $Q$ of the same set satisfy a local constraint that links neighboring elements of $Q$ through the mapping defined by $P$.
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CF 103446E - Strange Integers

We are given a sequence of integers and a threshold value $k$. From this sequence, we want to select a subsequence (preserving original indices) such that every pair of chosen values is “close” in value: the absolute difference between any two chosen elements must be at most…
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CF 103446D - Strange Fractions

We are given a fraction $frac{p}{q}$ and need to determine whether it can be represented in a very specific symmetric form involving two positive integers $a$ and $b$. The task is to either construct such a pair or report that it is impossible.
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CF 103446C - Strange Matrices

We are given a very small grid, at most 8 by 8, where each cell is either fixed as 0, fixed as 1, or flexible and marked as 2. Every 2 can independently become either 0 or 1, so the final matrix is chosen by deciding all those replacements.
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CF 103446A - Strange Functions

Each item gives a function indexed by $i$, defined by two parameters $ki$ and $ai$. The function is periodic in $x$, and its shape is determined by a transformed tangent expression involving $sec(x-ai)$.
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