freeCodeCamp/curriculum/challenges/english/02-javascript-algorithms-and-data-structures/regular-expressions/specify-upper-and-lower-number-of-matches.english.md

id, title, challengeType, forumTopicId

id	title	challengeType	forumTopicId
587d7db9367417b2b2512ba5	Specify Upper and Lower Number of Matches	1	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 quantity specifiers. 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/.

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.

Tests

tests:
  - text: Your regex should use curly brackets.
    testString: assert(ohRegex.source.match(/{.*?}/).length > 0);
  - text: Your regex should not match <code>"Ohh no"</code>
    testString: assert(!ohRegex.test("Ohh no"));
  - text: Your regex should match <code>"Ohhh no"</code>
    testString: assert("Ohhh no".match(ohRegex)[0].length === 7);
  - text: Your regex should match <code>"Ohhhh no"</code>
    testString: assert("Ohhhh no".match(ohRegex)[0].length === 8);
  - text: Your regex should match <code>"Ohhhhh no"</code>
    testString: assert("Ohhhhh no".match(ohRegex)[0].length === 9);
  - text: Your regex should match <code>"Ohhhhhh no"</code>
    testString: assert("Ohhhhhh no".match(ohRegex)[0].length === 10);
  - text: Your regex should not match <code>"Ohhhhhhh no"</code>
    testString: assert(!ohRegex.test("Ohhhhhhh no"));

Challenge Seed

let ohStr = "Ohhh no";
let ohRegex = /change/; // Change this line
let result = ohRegex.test(ohStr);

Solution

let ohStr = "Ohhh no";
let ohRegex = /Oh{3,6} no/; // Change this line
let result = ohRegex.test(ohStr);