wehub-resource-sync
dde272c4b8
i18n - Build Validation / Validate i18n Builds (24) (push) Has been cancelled
CI - Node.js / Lint (24) (push) Has been cancelled
CI - Node.js / Build (24) (push) Has been cancelled
CI - Node.js / Test (24) (push) Has been cancelled
CI - Node.js / Test - Upcoming Changes (24) (push) Has been cancelled
CI - Node.js / Test - i18n (italian, 24) (push) Has been cancelled
CI - Node.js / Test - i18n (portuguese, 24) (push) Has been cancelled
CD - Docker - GHCR Images / Build and Push Images (push) Has been cancelled
86 lines
2.2 KiB
Markdown
86 lines
2.2 KiB
Markdown
---
|
|
id: 6a0dcd03ee4e68698080ef68
|
|
title: "Challenge 304: Itinerary Arrangements"
|
|
challengeType: 29
|
|
dashedName: challenge-304
|
|
---
|
|
|
|
# --description--
|
|
|
|
Given an array of at least two optional stops for a day trip, return the number of valid itinerary arrangements.
|
|
|
|
The itinerary always includes `"breakfast"`, `"lunch"`, and `"dinner"`, these will not be passed in as arguments. The optional stops can be placed anywhere in the itinerary, subject to the following rules:
|
|
|
|
- `"breakfast"` is always first, with at least one stop before `"lunch"`.
|
|
- `"lunch"` must appear before `"dinner"`, with at least one stop in between.
|
|
- At most, one optional stop may appear after `"dinner"`.
|
|
|
|
Return the number of valid arrangements.
|
|
|
|
# --hints--
|
|
|
|
`get_itinerary_count(["library", "park"])` should return `2`.
|
|
|
|
```js
|
|
({test: () => { runPython(`
|
|
from unittest import TestCase
|
|
TestCase().assertEqual(get_itinerary_count(["library", "park"]), 2)`)
|
|
}})
|
|
```
|
|
|
|
`get_itinerary_count(["library", "park", "arcade"])` should return `18`.
|
|
|
|
```js
|
|
({test: () => { runPython(`
|
|
from unittest import TestCase
|
|
TestCase().assertEqual(get_itinerary_count(["library", "park", "arcade"]), 18)`)
|
|
}})
|
|
```
|
|
|
|
`get_itinerary_count(["library", "park", "arcade", "store"])` should return `120`.
|
|
|
|
```js
|
|
({test: () => { runPython(`
|
|
from unittest import TestCase
|
|
TestCase().assertEqual(get_itinerary_count(["library", "park", "arcade", "store"]), 120)`)
|
|
}})
|
|
```
|
|
|
|
`get_itinerary_count(["library", "park", "arcade", "store", "cafe"])` should return `840`.
|
|
|
|
```js
|
|
({test: () => { runPython(`
|
|
from unittest import TestCase
|
|
TestCase().assertEqual(get_itinerary_count(["library", "park", "arcade", "store", "cafe"]), 840)`)
|
|
}})
|
|
```
|
|
|
|
`get_itinerary_count(["library", "park", "arcade", "store", "cafe", "market", "museum"])` should return `55440`.
|
|
|
|
```js
|
|
({test: () => { runPython(`
|
|
from unittest import TestCase
|
|
TestCase().assertEqual(get_itinerary_count(["library", "park", "arcade", "store", "cafe", "market", "museum"]), 55440)`)
|
|
}})
|
|
```
|
|
|
|
# --seed--
|
|
|
|
## --seed-contents--
|
|
|
|
```py
|
|
def get_itinerary_count(stops):
|
|
|
|
return stops
|
|
```
|
|
|
|
# --solutions--
|
|
|
|
```py
|
|
from math import factorial
|
|
|
|
def get_itinerary_count(stops):
|
|
n = len(stops)
|
|
return (2 * n - 3) * factorial(n)
|
|
```
|