--- id: 587d7db9367417b2b2512ba7 title: Specify Exact Number of Matches challengeType: 1 forumTopicId: 301365 dashedName: specify-exact-number-of-matches --- # --description-- You can specify the lower and upper number of patterns with quantity specifiers using curly brackets. Sometimes you only want a specific number of matches. To specify a certain number of patterns, just have that one number between the curly brackets. For example, to match only the word `hah` with the letter `a` `3` times, your regex would be `/ha{3}h/`. ```js let A4 = "haaaah"; let A3 = "haaah"; let A100 = "h" + "a".repeat(100) + "h"; let multipleHA = /ha{3}h/; multipleHA.test(A4); multipleHA.test(A3); multipleHA.test(A100); ``` In order, the three `test` calls would return `false`, `true`, and `false`. # --instructions-- Change the regex `timRegex` to match the word `Timber` only when it has four letter `m`'s. # --hints-- Your regex should use curly brackets. ```js assert(timRegex.source.match(/{.*?}/).length > 0); ``` Your regex should not match the string `Timber` ```js timRegex.lastIndex = 0; assert(!timRegex.test('Timber')); ``` Your regex should not match the string `Timmber` ```js timRegex.lastIndex = 0; assert(!timRegex.test('Timmber')); ``` Your regex should not match the string `Timmmber` ```js timRegex.lastIndex = 0; assert(!timRegex.test('Timmmber')); ``` Your regex should match the string `Timmmmber` ```js timRegex.lastIndex = 0; assert(timRegex.test('Timmmmber')); ``` Your regex should not match the string `Timber` with 30 `m`'s in it. ```js timRegex.lastIndex = 0; assert(!timRegex.test('Ti' + 'm'.repeat(30) + 'ber')); ``` # --seed-- ## --seed-contents-- ```js let timStr = "Timmmmber"; let timRegex = /change/; // Change this line let result = timRegex.test(timStr); ``` # --solutions-- ```js let timStr = "Timmmmber"; let timRegex = /Tim{4}ber/; // Change this line let result = timRegex.test(timStr); ```