189 lines
2.9 KiB
Markdown
189 lines
2.9 KiB
Markdown
---
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id: 594dc6c729e5700999302b45
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title: Balanced brackets
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challengeType: 5
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forumTopicId: 302230
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dashedName: balanced-brackets
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---
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# --description--
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Determine whether a generated string of brackets is balanced; that is, whether it consists entirely of pairs of opening/closing brackets (in that order), none of which mis-nest.
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**Examples:**
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| Input | Output |
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| ------------------------- | ------ |
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| <code>\[]</code> | true |
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| <code>]\[</code> | false |
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| <code>[][]</code> | true |
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| <code>]\[]</code> | false |
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| <code>\[]]\[\[]</code> | false |
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| <code>\[\[\[\[]]]]</code> | true |
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# --hints--
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`isBalanced` should be a function.
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```js
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assert(typeof isBalanced === 'function');
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```
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`isBalanced("[]")` should return true.
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```js
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assert(isBalanced(testCases[0]));
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```
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`isBalanced("]][[[][][][]][")` should return false.
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```js
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assert(!isBalanced(testCases[1]));
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```
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`isBalanced("[][[[[][][[[]]]]]]")` should return true.
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```js
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assert(isBalanced(testCases[2]));
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```
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`isBalanced("][")` should return false.
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```js
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assert(!isBalanced(testCases[3]));
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```
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`isBalanced("[[[]]]][[]")` should return false.
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```js
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assert(!isBalanced(testCases[4]));
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```
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`isBalanced("][[]")` should return false.
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```js
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assert(!isBalanced(testCases[5]));
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```
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`isBalanced("][[][]][[[]]")` should return false.
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```js
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assert(!isBalanced(testCases[6]));
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```
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`isBalanced("[[][]]][")` should return false.
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```js
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assert(!isBalanced(testCases[7]));
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```
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`isBalanced("[[[]]][[]]]][][[")` should return false.
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```js
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assert(!isBalanced(testCases[8]));
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```
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`isBalanced("[]][[]]][[[[][]]")` should return false.
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```js
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assert(!isBalanced(testCases[9]));
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```
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`isBalanced("][]][[][")` should return false.
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```js
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assert(!isBalanced(testCases[10]));
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```
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`isBalanced("[[]][[][]]")` should return true.
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```js
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assert(isBalanced(testCases[11]));
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```
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`isBalanced("[[]]")` should return true.
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```js
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assert(isBalanced(testCases[12]));
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```
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`isBalanced("]][]][[]][[[")` should return false.
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```js
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assert(!isBalanced(testCases[13]));
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```
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`isBalanced("][]][][[")` should return false.
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```js
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assert(!isBalanced(testCases[14]));
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```
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`isBalanced("][][")` should return false.
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```js
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assert(!isBalanced(testCases[15]));
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```
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`isBalanced("[]]]")` should return false.
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```js
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assert(!isBalanced(testCases[16]));
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```
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`isBalanced("")` should return true.
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```js
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assert(isBalanced(testCases[17]));
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```
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# --seed--
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## --after-user-code--
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```js
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const testCases = [
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'[]',
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']][[[][][][]][',
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'[][[[[][][[[]]]]]]',
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'][',
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'[[[]]]][[]',
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'][[]',
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'][[][]][[[]]',
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'[[][]]][',
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'[[[]]][[]]]][][[',
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'[]][[]]][[[[][]]',
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'][]][[][',
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'[[]][[][]]',
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'[[]]',
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']][]][[]][[[',
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'][]][][[',
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'][][',
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'[]]]',
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''
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];
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```
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## --seed-contents--
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```js
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function isBalanced(str) {
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return true;
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}
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```
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# --solutions--
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```js
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function isBalanced(str) {
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if (str === '') return true;
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let a = str;
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let b;
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do {
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b = a;
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a = a.replace(/\[\]/g, '');
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} while (a !== b);
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return !a;
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}
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```
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