d269909faa
* fix: clean-up Project Euler 381-400 * fix: missing image extension * fix: missing subscripts Co-authored-by: Tom <20648924+moT01@users.noreply.github.com> Co-authored-by: Tom <20648924+moT01@users.noreply.github.com>
47 lines
900 B
Markdown
47 lines
900 B
Markdown
---
|
||
id: 5900f4f61000cf542c510008
|
||
title: 'Problem 393: Migrating ants'
|
||
challengeType: 5
|
||
forumTopicId: 302058
|
||
dashedName: problem-393-migrating-ants
|
||
---
|
||
|
||
# --description--
|
||
|
||
An $n × n$ grid of squares contains $n^2$ ants, one ant per square.
|
||
|
||
All ants decide to move simultaneously to an adjacent square (usually 4 possibilities, except for ants on the edge of the grid or at the corners).
|
||
|
||
We define $f(n)$ to be the number of ways this can happen without any ants ending on the same square and without any two ants crossing the same edge between two squares.
|
||
|
||
You are given that $f(4) = 88$.
|
||
|
||
Find $f(10)$.
|
||
|
||
# --hints--
|
||
|
||
`migratingAnts()` should return `112398351350823100`.
|
||
|
||
```js
|
||
assert.strictEqual(migratingAnts(), 112398351350823100);
|
||
```
|
||
|
||
# --seed--
|
||
|
||
## --seed-contents--
|
||
|
||
```js
|
||
function migratingAnts() {
|
||
|
||
return true;
|
||
}
|
||
|
||
migratingAnts();
|
||
```
|
||
|
||
# --solutions--
|
||
|
||
```js
|
||
// solution required
|
||
```
|