2019-2020 ICPC Southwestern European Regional Programming Contest (SWERC 2019-20)
12 problems from 2019-2020 ICPC Southwestern European Regional Programming Contest (SWERC 2019-20) (contest 102501), difficulty -. 12/12 solutions verified against sample I/O.
2019-2020 ICPC Southwestern European Regional Programming Contest (SWERC 2019-20)
ICPC/IOI | 12 problems | 12/12 verified | Difficulty - | 36m 56s
| # | Problem | Rating | Tags | Accepted | Time | ✓ |
|---|---|---|---|---|---|---|
| A | Environment-Friendly Travel | 1m 1s | ✓ | |||
| B | Biodiversity | 1m 5s | ✓ | |||
| C | Ants | 57s | ✓ | |||
| D | Gnalcats | 17m 7s | ✓ | |||
| E | Pixels | 1m | ✓ | |||
| F | Icebergs | 1m 5s | ✓ | |||
| G | Swapping Places | 1m 17s | ✓ | |||
| H | Pseudo-Random Number Generator | 1m 36s | ✓ | |||
| I | Rats | 3m 9s | ✓ | |||
| J | Counting Trees | 1m 26s | ✓ | |||
| K | Birdwatching | 54s | ✓ | |||
| L | River Game | 6m 19s | ✓ |
CF 102501A - Environment-Friendly Travel
We need choose a route from a starting coordinate to a destination coordinate. The route may use the car only for the first and last parts of the trip.
CF 102501E - Pixels
We have a rectangular binary grid. A cell is either black or white, and we need to choose a set of cells whose switches are pressed. Pressing one switch toggles that cell and its four orthogonal neighbours.
CF 102501K - Birdwatching
I will provide a compact version of the editorial that keeps the core reasoning, proof, implementation, and testing guidance while fitting the response limits. Edit We are given a directed graph of observed bird movements.
CF 102501H - Pseudo-Random Number Generator
The generator starts from a fixed 40-bit value and repeatedly transforms it into the next value. The transformation adds the current value, the value obtained by removing its lowest 20 bits, and a constant, then keeps only the lowest 40 bits.
CF 102501F - Icebergs
Edit We are given several icebergs, where each iceberg is described by the ordered list of points on its border. The points form a simple polygon, meaning the border never crosses itself.
CF 102501C - Ants
The task is to recover the next identifier that the ant identification program would assign. The input describes the identifiers currently seen by the recognition system.
CF 102501J - Counting Trees
The input is an inorder listing of the heights of a tree. Every possible variety corresponds to one binary tree whose nodes, read from left to right, have exactly this sequence of heights.
CF 102501G - Swapping Places
We are given a sequence of animal species representing the order in which animals enter a waiting line. The final leaving order is not fixed because neighboring animals are allowed to exchange places when their species pair is listed as compatible.
CF 102501D - Gnalcats
A gene is a short program that modifies the beginning of an extremely long chain of amino acids. The input contains two such programs, and the task is to decide whether they always behave identically on every sufficiently long chain of simple amino acids.
CF 102501B - Biodiversity
The input describes a census of animals in a garden. Each line after the first contains the name of one species. The task is to find whether one species has a population strictly larger than the combined population of every other species.
CF 102501L - River Game
The grid describes a wetland where cells form rivers. A connected group of cells is one river area. Cameras can only be placed on . cells that touch one of these river areas, and two cameras touching the same river area cannot be adjacent.
CF 102501I - Rats
Douglas performs a classic capture and recapture experiment to estimate the size of a rat population. On the first day, he catches n1 rats, marks all of them, and releases them. On the second day, he catches n2 rats, among which n12 are already marked.