2021-02-06 04:42:36 +00:00
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---
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id: bd7123c9c452eddfaeb5bdef
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2021-03-15 14:01:16 -06:00
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title: Utiliza la notación de corchetes para encontrar el carácter enésimo final en una cadena
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2021-02-06 04:42:36 +00:00
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challengeType: 1
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videoUrl: 'https://scrimba.com/c/cw4vkh9'
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forumTopicId: 18344
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dashedName: use-bracket-notation-to-find-the-nth-to-last-character-in-a-string
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---
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# --description--
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2021-03-15 14:01:16 -06:00
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Puedes usar el mismo principio que acabamos de usar para recuperar el último carácter de una cadena para recuperar el carácter enésimo final.
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2021-10-31 23:08:44 -07:00
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Por ejemplo, puedes obtener el valor de la antepenúltima letra de la cadena `const firstName = "Augusta"` usando `firstName[firstName.length - 3]`
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2021-03-15 14:01:16 -06:00
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Ejemplo:
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```js
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const firstName = "Augusta";
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const thirdToLastLetter = firstName[firstName.length - 3];
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```
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2021-06-05 00:07:40 +09:00
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`thirdToLastLetter` tendrá una cadena con valor `s`.
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2021-02-06 04:42:36 +00:00
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# --instructions--
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2021-03-15 14:01:16 -06:00
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Usa <dfn>notación de corchetes</dfn> para encontrar el penúltimo carácter en la cadena `lastName`.
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2021-03-15 14:01:16 -06:00
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**Sugerencia:** Intenta mirar el ejemplo de arriba si te quedas atascado.
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# --hints--
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2021-03-15 14:01:16 -06:00
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`secondToLastLetterOfLastName` debe ser la letra `c`.
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2021-02-06 04:42:36 +00:00
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```js
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assert(secondToLastLetterOfLastName === 'c');
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```
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2021-03-15 14:01:16 -06:00
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Debes usar `.length` para obtener la penúltima letra.
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2021-02-06 04:42:36 +00:00
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```js
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assert(code.match(/\.length/g).length > 0);
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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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(function(v){return v;})(secondToLastLetterOfLastName);
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```
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## --seed-contents--
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```js
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// Setup
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const lastName = "Lovelace";
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// Only change code below this line
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const secondToLastLetterOfLastName = lastName; // Change this line
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```
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# --solutions--
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```js
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const lastName = "Lovelace";
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const secondToLastLetterOfLastName = lastName[lastName.length - 2];
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```
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