2020-2021 ICPC, Moscow Subregional

14 problems from 2020-2021 ICPC, Moscow Subregional (contest 104842), difficulty -. 10/14 solutions verified against sample I/O.

14 items

2020-2021 ICPC, Moscow Subregional

ICPC/IOI | 14 problems | 10/14 verified | Difficulty - | 11m 45s

# Problem Rating Tags Accepted Time ✓
A Adventure in Flatland 47s ✓
B Basketball Plus-Minus 57s ✓
C C and Pascal Strings 37s
D Deep Primes 29s
E Easy Money 57s ✓
F Fun at Luggage Claim 49s ✓
G Game With Stones 26s
H Hungry Cannibals 21s
I Integer Number Format 1m 11s ✓
J Just Different Rules... 57s ✓
K King and Zeroing 1m 10s ✓
L Linear Algebra Intensifies 48s ✓
M Matrix 4 59s ✓
N New Randomized Go 1m 17s ✓
Practice › Codeforces Solutions › 2020-2021 ICPC, Moscow Subregional ›

CF 104842N - New Randomized Go

We are given $n$ distinct points placed on a circle of circumference $l$. Each point lies on the boundary, and its position is given as a coordinate along the circle. After that, each point is independently colored red or blue with probability $1/2$.
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CF 104842M - Matrix 4

We start at a fixed 2×2 identity matrix and want to reach a target 2×2 integer matrix. Each move corresponds to multiplying the current matrix on the right by one of four fixed 2×2 matrices.
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CF 104842K - King and Zeroing

We are given a tree with n cities connected by n − 1 undirected roads. Every road normally costs 1 credit to traverse in either direction.
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CF 104842L - Linear Algebra Intensifies

We are given a collection of intervals on the line from 1 to n. Each interval contributes to a symmetric n by n matrix in a very specific way: for any pair of indices x and y, we count how many of the given intervals simultaneously cover both x and y, and that count becomes…
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CF 104842I - Integer Number Format

We are asked to design a custom integer encoding system for a fixed bit-based format. Each number is encoded using a leading 4-bit selector, followed by zero to four additional 4-bit groups.
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CF 104842J - Just Different Rules...

Each card in this problem belongs to a lane and has two independent attributes: a rank from 1 to n, and a color which is either white or black. A lane is just a multiset of such cards.
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CF 104842H - Hungry Cannibals

We are given a group of people trying to cross a river using a very small boat. There are two types of people: cannibals and missionaries.
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CF 104842F - Fun at Luggage Claim

We are given a circular array of length $n$. Each position initially contains some number of items, and we are allowed to redistribute these items using a very specific local operation.
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CF 104842E - Easy Money

We are given a very large integer, but instead of treating it as a number, we should think of it as a multiset of decimal digits. Bomboslav removes all digits from the cheque and wants to reassemble them into a new integer using every digit exactly once.
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CF 104842G - Game With Stones

We are given a line of $n$ boxes and several initial configurations of $m$ identical stones distributed across them. Each configuration is simply an array of $n$ nonnegative integers whose sum is fixed to $m$.
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CF 104842D - Deep Primes

We are looking at integers written in decimal form, but the key constraint is not about their numeric value alone. Each number is interpreted as a string, and every contiguous block of digits inside that string is turned back into an integer by stripping leading zeros.
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CF 104842B - Basketball Plus-Minus

The game simulates a basketball match where two teams each start with five active players and five substitutes. Over time, two things happen: players are swapped between the court and the bench, and scoring events occur.
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CF 104842A - Adventure in Flatland

We are given two points on an integer grid. Both the starting point and the destination lie strictly away from the coordinate axes, meaning neither coordinate is zero at either endpoint. Such points are called free points.
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CF 104842C - C and Pascal Strings

We are given a sequence of bytes, each written as a two-digit hexadecimal number, so each value lies in the range from 0 to 255.
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