107 lines
2.4 KiB
Markdown
107 lines
2.4 KiB
Markdown
---
|
|
id: 594810f028c0303b75339ad4
|
|
title: Word wrap
|
|
challengeType: 5
|
|
forumTopicId: 302344
|
|
dashedName: word-wrap
|
|
---
|
|
|
|
# --description--
|
|
|
|
Even today, with proportional fonts and complex layouts, there are still cases where you need to wrap text at a specified column. The basic task is to wrap a paragraph of text in a simple way.
|
|
|
|
# --instructions--
|
|
|
|
Write a function that can wrap this text to any number of characters. As an example, the text wrapped to 80 characters should look like the following:
|
|
|
|
<pre>
|
|
Wrap text using a more sophisticated algorithm such as the Knuth and Plass TeX
|
|
algorithm. If your language provides this, you get easy extra credit, but you
|
|
must reference documentation indicating that the algorithm is something better
|
|
than a simple minimum length algorithm.
|
|
</pre>
|
|
|
|
# --hints--
|
|
|
|
wrap should be a function.
|
|
|
|
```js
|
|
assert.equal(typeof wrap, 'function');
|
|
```
|
|
|
|
wrap should return a string.
|
|
|
|
```js
|
|
assert.equal(typeof wrap('abc', 10), 'string');
|
|
```
|
|
|
|
wrap(80) should return 4 lines.
|
|
|
|
```js
|
|
assert(wrapped80.split('\n').length === 4);
|
|
```
|
|
|
|
Your `wrap` function should return our expected text.
|
|
|
|
```js
|
|
assert.equal(wrapped80.split('\n')[0], firstRow80);
|
|
```
|
|
|
|
wrap(42) should return 7 lines.
|
|
|
|
```js
|
|
assert(wrapped42.split('\n').length === 7);
|
|
```
|
|
|
|
Your `wrap` function should return our expected text.
|
|
|
|
```js
|
|
assert.equal(wrapped42.split('\n')[0], firstRow42);
|
|
```
|
|
|
|
# --seed--
|
|
|
|
## --after-user-code--
|
|
|
|
```js
|
|
const text =
|
|
`Wrap text using a more sophisticated algorithm such as the Knuth and Plass TeX algorithm.
|
|
If your language provides this, you get easy extra credit,
|
|
but you ''must reference documentation'' indicating that the algorithm
|
|
is something better than a simple minimum length algorithm.`;
|
|
|
|
const wrapped80 = wrap(text, 80);
|
|
const wrapped42 = wrap(text, 42);
|
|
|
|
const firstRow80 =
|
|
'Wrap text using a more sophisticated algorithm such as the Knuth and Plass TeX';
|
|
|
|
const firstRow42 = 'Wrap text using a more sophisticated';
|
|
```
|
|
|
|
## --seed-contents--
|
|
|
|
```js
|
|
function wrap(text, limit) {
|
|
return text;
|
|
}
|
|
```
|
|
|
|
# --solutions--
|
|
|
|
```js
|
|
function wrap(text, limit) {
|
|
const noNewlines = text.replace('\n', '');
|
|
if (noNewlines.length > limit) {
|
|
// find the last space within limit
|
|
const edge = noNewlines.slice(0, limit).lastIndexOf(' ');
|
|
if (edge > 0) {
|
|
const line = noNewlines.slice(0, edge);
|
|
const remainder = noNewlines.slice(edge + 1);
|
|
return line + '\n' + wrap(remainder, limit);
|
|
}
|
|
}
|
|
return text;
|
|
}
|
|
```
|