freeCodeCamp/curriculum/challenges/chinese/22-rosetta-code/rosetta-code-challenges/word-wrap.md

id, title, challengeType, forumTopicId, dashedName

id	title	challengeType	forumTopicId	dashedName
594810f028c0303b75339ad4	自动换行	1	302344	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:

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.

--hints--

任务：

assert.equal(typeof wrap, 'function');

例如，包装为80个字符的文本应如下所示：

assert.equal(typeof wrap('abc', 10), 'string');

wrap（42）必须返回7行。

assert(wrapped80.split('\n').length === 4);

wrap是一个功能。

assert.equal(wrapped80.split('\n')[0], firstRow80);

wrap(42) 应该返回 7 行。

assert(wrapped42.split('\n').length === 7);

你的 wrap 函数应该返回我们预期的文本。

assert.equal(wrapped42.split('\n')[0], firstRow42);

--seed--

--after-user-code--

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--

function wrap(text, limit) {
  return text;
}

--solutions--

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;
}