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freeCodeCamp/curriculum/challenges/english/02-javascript-algorithms-and-data-structures/regular-expressions/find-characters-with-lazy-matching.md
Nicholas Carrigan (he/him) 7117919d36 chore(learn): audit javascript algorithms and data structures (#41092)
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Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com>
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Co-authored-by: Oliver Eyton-Williams <ojeytonwilliams@gmail.com>
2021-03-02 17:12:12 -07:00

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---
id: 587d7db6367417b2b2512b9b
title: Find Characters with Lazy Matching
challengeType: 1
forumTopicId: 301341
dashedName: find-characters-with-lazy-matching
---
# --description--
In regular expressions, a <dfn>greedy</dfn> match finds the longest possible part of a string that fits the regex pattern and returns it as a match. The alternative is called a <dfn>lazy</dfn> match, which finds the smallest possible part of the string that satisfies the regex pattern.
You can apply the regex `/t[a-z]*i/` to the string `"titanic"`. This regex is basically a pattern that starts with `t`, ends with `i`, and has some letters in between.
Regular expressions are by default greedy, so the match would return `["titani"]`. It finds the largest sub-string possible to fit the pattern.
However, you can use the `?` character to change it to lazy matching. `"titanic"` matched against the adjusted regex of `/t[a-z]*?i/` returns `["ti"]`.
**Note:** Parsing HTML with regular expressions should be avoided, but pattern matching an HTML string with regular expressions is completely fine.
# --instructions--
Fix the regex `/<.*>/` to return the HTML tag `<h1>` and not the text `"<h1>Winter is coming</h1>"`. Remember the wildcard `.` in a regular expression matches any character.
# --hints--
The `result` variable should be an array with `<h1>` in it
```js
assert(result[0] == '<h1>');
```
`myRegex` should use lazy matching
```js
assert(/\?/g.test(myRegex));
```
`myRegex` should not include the string `h1`
```js
assert(!myRegex.source.match('h1'));
```
# --seed--
## --seed-contents--
```js
let text = "<h1>Winter is coming</h1>";
let myRegex = /<.*>/; // Change this line
let result = text.match(myRegex);
```
# --solutions--
```js
let text = "<h1>Winter is coming</h1>";
let myRegex = /<.*?>/; // Change this line
let result = text.match(myRegex);
```