freeCodeCamp/curriculum/challenges/english/02-javascript-algorithms-an.../regular-expressions/specify-upper-and-lower-num...

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---
id: 587d7db9367417b2b2512ba5
title: Specify Upper and Lower Number of Matches
challengeType: 1
forumTopicId: 301367
---
# --description--
Recall that you use the plus sign `+` to look for one or more characters and the asterisk `*` to look for zero or more characters. These are convenient but sometimes you want to match a certain range of patterns.
You can specify the lower and upper number of patterns with <dfn>quantity specifiers</dfn>. Quantity specifiers are used with curly brackets (`{` and `}`). You put two numbers between the curly brackets - for the lower and upper number of patterns.
For example, to match only the letter `a` appearing between `3` and `5` times in the string `"ah"`, your regex would be `/a{3,5}h/`.
```js
let A4 = "aaaah";
let A2 = "aah";
let multipleA = /a{3,5}h/;
multipleA.test(A4); // Returns true
multipleA.test(A2); // Returns false
```
# --instructions--
Change the regex `ohRegex` to match the entire phrase `"Oh no"` only when it has `3` to `6` letter `h`'s.
# --hints--
Your regex should use curly brackets.
```js
assert(ohRegex.source.match(/{.*?}/).length > 0);
```
Your regex should not match `"Ohh no"`
```js
assert(!ohRegex.test('Ohh no'));
```
Your regex should match `"Ohhh no"`
```js
assert('Ohhh no'.match(ohRegex)[0].length === 7);
```
Your regex should match `"Ohhhh no"`
```js
assert('Ohhhh no'.match(ohRegex)[0].length === 8);
```
Your regex should match `"Ohhhhh no"`
```js
assert('Ohhhhh no'.match(ohRegex)[0].length === 9);
```
Your regex should match `"Ohhhhhh no"`
```js
assert('Ohhhhhh no'.match(ohRegex)[0].length === 10);
```
Your regex should not match `"Ohhhhhhh no"`
```js
assert(!ohRegex.test('Ohhhhhhh no'));
```
# --seed--
## --seed-contents--
```js
let ohStr = "Ohhh no";
let ohRegex = /change/; // Change this line
let result = ohRegex.test(ohStr);
```
# --solutions--
```js
let ohStr = "Ohhh no";
let ohRegex = /Oh{3,6} no/; // Change this line
let result = ohRegex.test(ohStr);
```