2022-2023 CTU Open Contest

12 problems from 2022-2023 CTU Open Contest (contest 104673), difficulty -. 12/12 solutions verified against sample I/O.

12 items

2022-2023 CTU Open Contest

Special | 12 problems | 12/12 verified | Difficulty - | 11m 34s

#	Problem	Time	✓
A	Array	54s	✓
B	Canoes	1m 16s	✓
C	Earthquake	48s	✓
D	Journals	52s	✓
E	Mower	57s	✓
F	Needle	55s	✓
G	Patio	49s	✓
H	Robots	1m 9s	✓
I	Shamans	1m 6s	✓
J	Transmitter	59s	✓
K	Volcanoes	1m 6s	✓
L	Wagon	43s	✓

Practice › Codeforces Solutions › 2022-2023 CTU Open Contest ›

CF 104673J - Transmitter

We are given a vertical stack of transmitters, each described by a string over lowercase letters. Each transmitter emits a sequence over time, one character per second, and after its string ends it stops emitting coordination signals but still remains present.

Practice › Codeforces Solutions › 2022-2023 CTU Open Contest ›

CF 104673C - Earthquake

We are given a fixed database of clean phone numbers, each consisting of exactly nine digits. Alongside this, we receive many query strings that represent damaged versions of phone numbers. Some digits in these query strings are missing because of stains.

Practice › Codeforces Solutions › 2022-2023 CTU Open Contest ›

CF 104673K - Volcanoes

We are given a set of points in the plane, each representing a volcano that must be visited exactly once. A traveler starts from any chosen point and must construct a path that visits all points and then ends at the last visited point.

Practice › Codeforces Solutions › 2022-2023 CTU Open Contest ›

CF 104673L - Wagon

A train moves through a sequence of cities in a fixed order, and at each city there are a few crane types available, each with a price. Every crane type is identified by an ID, and in a given city you may buy or sell any of the types listed there at that city’s price.

Practice › Codeforces Solutions › 2022-2023 CTU Open Contest ›

CF 104673I - Shamans

We are given a grid made of empty cells and cells occupied by a single connected polyomino, represented by . The shape is fixed and cannot be altered except by cutting along grid edges. The process works like this: we repeatedly remove pieces from the shape.

Practice › Codeforces Solutions › 2022-2023 CTU Open Contest ›

CF 104673H - Robots

We are working on a graph of villages connected by undirected roads. One robot, which we control, starts at a village S and wants to reach a target village F. It moves only at night, and each night it can either traverse one road to a neighboring village or stay in place.

Practice › Codeforces Solutions › 2022-2023 CTU Open Contest ›

CF 104673G - Patio

We are given a long linear sequence of square tiles, each tile being either red or blue. We need to count how many contiguous segments of this sequence can be used to build a very specific square patio.

Practice › Codeforces Solutions › 2022-2023 CTU Open Contest ›

CF 104673F - Needle

We are given a set of disjoint “clouds”, where each cloud is a set of points whose convex hull forms a simple convex polygon. These polygons do not overlap in their interiors, and they may touch only in empty space, never intersecting each other.

Practice › Codeforces Solutions › 2022-2023 CTU Open Contest ›

CF 104673E - Mower

We are given a very large rectangular grid of size $W times H$. Each cell is initially unvisited. A single starting cell $(X, Y)$ is already marked as visited before the game begins. From that moment on, two players alternate moves, starting with the first player.

Practice › Codeforces Solutions › 2022-2023 CTU Open Contest ›

CF 104673D - Journals

We are given a stack of journals represented by a string of + and -, where each symbol describes the orientation of a journal cover. The stack is read from top to bottom as the string is given.

Practice › Codeforces Solutions › 2022-2023 CTU Open Contest ›

CF 104673B - Canoes

We are given a rectangular grid that represents a shoreline, and inside this grid there are many “docks”. Each dock is a 1-cell-thick straight segment aligned either horizontally or vertically, and it spans a contiguous set of grid cells. Each dock has length at least two.

Practice › Codeforces Solutions › 2022-2023 CTU Open Contest ›

CF 104673A - Array

The structure described in the problem is a triangular grid of cells, where each row is longer than the previous one by exactly one cell. The first row contains a single cell, and every subsequent row extends symmetrically.