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---
id: 56bbb991ad1ed5201cd392ce
title: Manipulate Arrays With unshift()
localeTitle: Manipular matrices con unshift ()
challengeType: 1
---
## Description
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< section id = 'description' >
No solo puede < code > shift< / code > elementos del principio de una matriz, < code > unshift< / code > también puede < code > unshift< / code > elementos al principio de una matriz, es decir, agregar elementos delante de la matriz.
< code > .unshift()< / code > funciona exactamente como < code > .push()< / code > , pero en lugar de agregar el elemento al final de la matriz, < code > unshift()< / code > agrega el elemento al principio de la matriz.
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< / section >
## Instructions
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< section id = 'instructions' >
Añadir < code > [" Paul" ,35]< / code > para el inicio de la < code > myArray< / code > variable usando < code > unshift()< / code > .
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< / section >
## Tests
< section id = 'tests' >
```yml
tests:
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- text: ' < code > myArray</ code > debería tener ahora [[" Paul" , 35], [" dog" , 3]].'
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testString: 'assert((function(d){if(typeof d[0] === "object" & & d[0][0] == "Paul" & & d[0][1] === 35 & & d[1][0] != undefined & & d[1][0] == "dog" & & d[1][1] != undefined & & d[1][1] == 3){return true;}else{return false;}})(myArray), "< code > myArray< / code > should now have [["Paul", 35], ["dog", 3]].");'
```
< / section >
## Challenge Seed
< section id = 'challengeSeed' >
< div id = 'js-seed' >
```js
// Example
var ourArray = ["Stimpson", "J", "cat"];
ourArray.shift(); // ourArray now equals ["J", "cat"]
ourArray.unshift("Happy");
// ourArray now equals ["Happy", "J", "cat"]
// Setup
var myArray = [["John", 23], ["dog", 3]];
myArray.shift();
// Only change code below this line.
```
< / div >
### After Test
< div id = 'js-teardown' >
```js
console.info('after the test');
```
< / div >
< / section >
## Solution
< section id = 'solution' >
```js
var myArray = [["John", 23], ["dog", 3]];
myArray.shift();
myArray.unshift(["Paul", 35]);
```
< / section >