XXVI Interregional Programming Olympiad, Vologda SU, 2024

12 problems from XXVI Interregional Programming Olympiad, Vologda SU, 2024 (contest 105122), difficulty -. 5/12 solutions verified against sample I/O.

12 items

XXVI Interregional Programming Olympiad, Vologda SU, 2024

Special | 12 problems | 5/12 verified | Difficulty - | 17m

#	Problem	Time	✓
A	Generator	1m 30s
B	Bishop Paths	1m 27s
C	Brackets	1m 36s	✓
D	Virtual Memory	1m 32s
E	Last digit	1m 33s
F	Transportation of Details	1m 56s
G	Modest Numbers	1m 12s
H	Hirsch index	1m 21s	✓
I	Standard geometry problem	1m 40s
J	Game with stones	54s	✓
K	Game with stones, more difficult version	1m 3s	✓
L	Equality	1m 16s	✓

Practice › Codeforces Solutions › XXVI Interregional Programming Olympiad, Vologda SU, 2024 ›

CF 105122L - Equality

We are given a single line string that is meant to represent an arithmetic equality between two expressions. Each expression can contain decimal digits and the symbols + and -.

Practice › Codeforces Solutions › XXVI Interregional Programming Olympiad, Vologda SU, 2024 ›

CF 105122I - Standard geometry problem

We are given a set of points in the plane and asked to reconstruct the boundary of their convex hull in two different levels of detail.

Practice › Codeforces Solutions › XXVI Interregional Programming Olympiad, Vologda SU, 2024 ›

CF 105122K - Game with stones, more difficult version

We are looking at a two-player impartial game played on a single pile of stones. The game starts with $N$ stones, and players alternate turns. On a turn, the current player removes between $1$ and $K$ stones inclusive.

Practice › Codeforces Solutions › XXVI Interregional Programming Olympiad, Vologda SU, 2024 ›

CF 105122J - Game with stones

We are playing a two-player take-away game with a single pile of stones. Players alternate turns, and on each turn a player removes between 1 and K stones inclusive.

Practice › Codeforces Solutions › XXVI Interregional Programming Olympiad, Vologda SU, 2024 ›

CF 105122H - Hirsch index

We are given a list of scientific papers, each with a current citation count. The Hirsch index we want to reach is a threshold H, which means we need at least H papers whose citation counts are each at least H.

Practice › Codeforces Solutions › XXVI Interregional Programming Olympiad, Vologda SU, 2024 ›

CF 105122G - Modest Numbers

We are asked to count integers in a range $[a, b]$ such that each integer has exactly seven positive divisors. The task is not about factoring arbitrary numbers efficiently online, but about understanding the structure of numbers whose divisor function equals seven.

Practice › Codeforces Solutions › XXVI Interregional Programming Olympiad, Vologda SU, 2024 ›

CF 105122F - Transportation of Details

We can view the factory as a directed graph on $N$ workshops. Every workshop from $1$ to $N-1$ already has exactly one outgoing conveyor, so each of these nodes points to a fixed next node. Workshop $N$ is newly introduced and initially has no outgoing conveyor.

Practice › Codeforces Solutions › XXVI Interregional Programming Olympiad, Vologda SU, 2024 ›

CF 105122E - Last digit

We are given a positive integer $n$, and we conceptually form a huge product where each integer $i$ from 1 to $n$ is raised to its own power $i$, and all these values are multiplied together: $$1^1 cdot 2^2 cdot 3^3 cdots n^n$$ The task is not to compute this enormous number…

Practice › Codeforces Solutions › XXVI Interregional Programming Olympiad, Vologda SU, 2024 ›

CF 105122D - Virtual Memory

We are simulating a simplified virtual memory system where pages can either be in fast physical memory or stored on disk. At the start, the first m pages are already loaded into physical memory, and the remaining pages are on disk. Then a sequence of k page accesses is executed.

Practice › Codeforces Solutions › XXVI Interregional Programming Olympiad, Vologda SU, 2024 ›

CF 105122B - Bishop Paths

We are given an $n times n$ chessboard and a bishop placed on a starting square. The bishop can move any number of cells in a single move, but only along diagonals.

Practice › Codeforces Solutions › XXVI Interregional Programming Olympiad, Vologda SU, 2024 ›

CF 105122C - Brackets

We are working with correctly balanced parentheses strings of length $2n$. Such a string can be thought of as a sequence of $n$ opening brackets and $n$ closing brackets arranged so that at every prefix, openings are never outnumbered by closings, and at the end the counts match.

Practice › Codeforces Solutions › XXVI Interregional Programming Olympiad, Vologda SU, 2024 ›

CF 105122A - Generator

We are asked to build a generator that outputs pairs of integers $(a, b)$ satisfying $1 le a le b le k$, and each valid pair must be produced with equal probability whenever we request a new value.