2018-2019 ICPC NERC (NEERC), North-Western Russia Regional Contest (Northern Subregionals)
12 problems from 2018-2019 ICPC NERC (NEERC), North-Western Russia Regional Contest (Northern Subregionals) (contest 104873), difficulty -. 11/12 solutions verified against sample I/O.
2018-2019 ICPC NERC (NEERC), North-Western Russia Regional Contest (Northern Subregionals)
ICPC/IOI | 12 problems | 11/12 verified | Difficulty - | 10m 50s
| # | Problem | Rating | Tags | Accepted | Time | ✓ |
|---|---|---|---|---|---|---|
| A | Accumulator Battery | 50s | ✓ | |||
| B | Building a Stair | 1m 5s | ✓ | |||
| C | Counting Stairs | 31s | ||||
| D | Distinct Substrings | 35s | ✓ | |||
| E | Email Destruction | 38s | ✓ | |||
| F | Forgotten Land | 1m 15s | ✓ | |||
| G | Generalized German Quotation | 45s | ✓ | |||
| H | Halves Not Equal | 35s | ✓ | |||
| I | Interactive Array Guessing | 1m 12s | ✓ | |||
| J | Joined Vessels | 1m 26s | ✓ | |||
| K | Keyboard Consensus | 48s | ✓ | |||
| L | LED-led Paths | 1m 10s | ✓ |
CF 104873J - Joined Vessels
We are given a line of vessels connected in a chain. Between vessel i and i+1 there is a narrow connection that only starts behaving like a proper communicating tube once the water level reaches a fixed height hi.
CF 104873E - Email Destruction
Each email belongs to a “thread” that evolves in a very rigid way. A thread starts from a base subject, which is a non-empty lowercase string. Every next email in the same thread is created by prepending the prefix "Re: " to the previous subject.
CF 104873L - LED-led Paths
We are given a directed acyclic graph where vertices represent junctions in a city and edges represent one-way streets. The acyclic condition means there is no way to start at a junction and follow directed streets to eventually return to the same place.
CF 104873K - Keyboard Consensus
We are given a set of n keyboards, each identified by an integer label. Two people, Kolya and Kostya, each rank all keyboards from most preferred to least preferred, and both rankings are known to both players. They play a deterministic elimination game.
CF 104873I - Interactive Array Guessing
We are given several hidden arrays, each containing a small number of distinct integers. The arrays are ordered from 1 to n, and each query lets us pick a list of indices and receive the concatenation of those arrays in that order, but without any separators between elements.
CF 104873H - Halves Not Equal
We are asked to split a fixed amount of gold among $n$ recipients, where each recipient $i$ has a declared maximum acceptable share $ai$. The total gold available is $s$, and it may be strictly smaller than the sum of all claims, so not everyone can receive what they want.
CF 104873F - Forgotten Land
We are given a tree with $n$ cities. Each city has exactly one language label from $1$ to $k$. The cities are partitioned into several disjoint groups, called alliances, but the partition is arbitrary and not restricted by edges of the tree.
CF 104873G - Generalized German Quotation
We are given a sequence made only of two kinds of quote tokens. Each token is either the left style written as << or the right style written as . The task is not to interpret them as fixed opening or closing brackets.
CF 104873D - Distinct Substrings
We are given a short string p and a very large integer n. The actual string we work with is not arbitrary: it is formed by repeating p over and over and then cutting it after exactly n characters.
CF 104873B - Building a Stair
We are asked to construct a particular shape made of unit cubes, drawn as a square grid. Each cell either contains a cube or is empty, and the occupied cells must form a “stair” shape.
CF 104873A - Accumulator Battery
A phone starts a journey fully charged and consumes battery while Anna travels. At some point during the journey, when the battery level hits a fixed threshold of 20 percent, the phone switches to a slower discharge mode.
CF 104873C - Counting Stairs
We are asked to count a specific class of shapes built from unit cubes. Each valid configuration is a “stair-like” structure: columns of cubes arranged from left to right with heights that never increase as we move right.