The 17th Chinese Northeast Collegiate Programming Contest

13 problems from The 17th Chinese Northeast Collegiate Programming Contest (contest 104366), difficulty -. 13/13 solutions verified against sample I/O.

13 items

The 17th Chinese Northeast Collegiate Programming Contest

Special | 13 problems | 13/13 verified | Difficulty - | 12m 21s

# Problem Rating Tags Accepted Time ✓
A Cask Effect 57s ✓
B Problem B 1m 2s ✓
C Abstract Painting 1m ✓
D Concrete Painting 53s ✓
E Triangle Pick 1m 6s ✓
F MPFT 56s ✓
G Expected Sum 53s ✓
H Light the Street 54s ✓
I Subsetting and Summing 55s ✓
J Less Time on the Road 1m 11s ✓
K The Secret Comparison 51s ✓
L Spatial Quantum Energy Theory 48s ✓
M Easy Problem of Prime 55s ✓
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CF 104366L - Spatial Quantum Energy Theory

We are given a system of atoms, where each atom is defined by a subset of at most 20 possible elementary particle types. Each particle type has a fixed energy value.
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CF 104366M - Easy Problem of Prime

We are given many independent queries. Each query provides a number $n$, and for that value we first imagine all integers from $2$ up to $n$. For each integer $i$, we define a value $f(i)$, where $f(i)$ is the smallest number of prime numbers whose sum equals exactly $i$.
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CF 104366J - Less Time on the Road

We are given a directed graph where every edge has unit cost, and the graph is guaranteed to be strongly connected. Two workers start at vertex 1. A sequence of requests arrives, and each request specifies a vertex that must be visited to perform a repair.
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CF 104366K - The Secret Comparison

Two competitors each have a single integer score. The task is to compare these two numbers and declare who has the higher score, or whether they are equal. The input consists of exactly two integers, representing the scores of the two players.
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CF 104366I - Subsetting and Summing

We are given a collection of 3D vectors. From these vectors we may choose any subset, including the empty set, and sum the chosen vectors component-wise to obtain a single resultant vector.
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CF 104366H - Light the Street

We are placing streetlights along a one-dimensional segment of length $n$. We are allowed to choose up to $k$ positions for these lights.
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CF 104366G - Expected Sum

We are given a long decimal string, interpreted as a sequence of digits placed left to right. Between every adjacent pair of digits, we independently decide whether to insert a plus sign.
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CF 104366E - Triangle Pick

We are given a collection of triangular surfaces in 3D space. Each triangle is a flat solid piece defined by three vertices.
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CF 104366F - MPFT

We are simulating a chat group that changes over time. People either join the group or send messages, and the group has strict rules that can forcibly remove members. The first rule is a capacity constraint. The group can hold at most N people.
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CF 104366D - Concrete Painting

We are given a collection of segments on a number line. From these segments, we consider every possible subset of them. For any chosen subset, we imagine painting all of its segments onto the number line, where overlapping parts are still counted only once.
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CF 104366B - Problem B

The town is a rectangular grid of intersections with roads connecting adjacent intersections in the usual four-direction structure. Vehicles enter from any boundary road endpoint and must eventually leave through some boundary endpoint.
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CF 104366C - Abstract Painting

We are given a collection of axis-aligned line segments on an infinite 2D plane. Each segment is either vertical or horizontal. Two segments are considered connected if they physically intersect at any point, including touching at endpoints.
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CF 104366A - Cask Effect

We are given several wooden boards, each with a fixed length. The “strength” or “capacity” of a cask built from these boards is defined as the length of the shortest board used in it.
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