107 lines
2.4 KiB
Markdown
107 lines
2.4 KiB
Markdown
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---
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id: 594810f028c0303b75339ad4
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title: Word wrap
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challengeType: 5
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forumTopicId: 302344
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dashedName: word-wrap
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---
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# --description--
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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.
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# --instructions--
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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:
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<pre>
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Wrap text using a more sophisticated algorithm such as the Knuth and Plass TeX
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algorithm. If your language provides this, you get easy extra credit, but you
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must reference documentation indicating that the algorithm is something better
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than a simple minimum length algorithm.
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</pre>
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# --hints--
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wrap should be a function.
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```js
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assert.equal(typeof wrap, 'function');
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```
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wrap should return a string.
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```js
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assert.equal(typeof wrap('abc', 10), 'string');
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```
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wrap(80) should return 4 lines.
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```js
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assert(wrapped80.split('\n').length === 4);
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```
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Your `wrap` function should return our expected text.
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```js
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assert.equal(wrapped80.split('\n')[0], firstRow80);
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```
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wrap(42) should return 7 lines.
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```js
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assert(wrapped42.split('\n').length === 7);
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```
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Your `wrap` function should return our expected text.
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```js
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assert.equal(wrapped42.split('\n')[0], firstRow42);
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```
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# --seed--
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## --after-user-code--
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```js
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const text =
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`Wrap text using a more sophisticated algorithm such as the Knuth and Plass TeX algorithm.
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If your language provides this, you get easy extra credit,
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but you ''must reference documentation'' indicating that the algorithm
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is something better than a simple minimum length algorithm.`;
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const wrapped80 = wrap(text, 80);
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const wrapped42 = wrap(text, 42);
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const firstRow80 =
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'Wrap text using a more sophisticated algorithm such as the Knuth and Plass TeX';
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const firstRow42 = 'Wrap text using a more sophisticated';
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```
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## --seed-contents--
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```js
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function wrap(text, limit) {
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return text;
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}
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```
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# --solutions--
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```js
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function wrap(text, limit) {
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const noNewlines = text.replace('\n', '');
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if (noNewlines.length > limit) {
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// find the last space within limit
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const edge = noNewlines.slice(0, limit).lastIndexOf(' ');
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if (edge > 0) {
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const line = noNewlines.slice(0, edge);
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const remainder = noNewlines.slice(edge + 1);
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return line + '\n' + wrap(remainder, limit);
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}
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}
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return text;
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}
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```
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