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@ -304,6 +304,7 @@ fill: Fill all the array elements with a static value
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```js
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const arr = Array() // creates an an empty array
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console.log(arr)
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const eightXvalues = Array(8).fill('X') // it creates eight element values
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console.log(eightXvalues) // ['X', 'X','X','X','X','X','X','X']
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@ -396,21 +397,23 @@ lastIndexOf:Give the position of the last item in the array. If it exist it retu
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```js
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const numbers = [1, 2, 3, 4, 5, 3, 1, 2]
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console.log(numbers.lastIndexOf(2)) // -> 7
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console.log(numbers.lastIndexOf(0)) // -> -1
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console.log(numbers.lastIndexOf(1)) // -> 6
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console.log(numbers.lastIndexOf(4)) // -> 3
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console.log(numbers.lastIndexOf(6)) // -> -1
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console.log(numbers.lastIndexOf(2)) // -7
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console.log(numbers.lastIndexOf(0)) // -1
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console.log(numbers.lastIndexOf(1)) // 6
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console.log(numbers.lastIndexOf(4)) // 3
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console.log(numbers.lastIndexOf(6)) // -1
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```
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includes:To check if an item exist in an array. If it exist it returns the true else it returns false.
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```js
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const numbers = [1, 2, 3, 4, 5]
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console.log(numbers.includes(5)) // -> true
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console.log(numbers.includes(0)) // -> false
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console.log(numbers.includes(1)) // -> true
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console.log(numbers.includes(6)) // -> false
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console.log(numbers.includes(5)) // true
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console.log(numbers.includes(0)) // false
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console.log(numbers.includes(1)) // true
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console.log(numbers.includes(6)) // false
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const webTechs = [
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'HTML',
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@ -432,9 +435,10 @@ Array.isArray:To check if the data type is an array
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```js
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const numbers = [1, 2, 3, 4, 5]
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console.log(Array.isArray(numbers)) // -> true
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console.log(Array.isArray(numbers)) // true
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const number = 100
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console.log(Array.isArray(number)) // -> false
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console.log(Array.isArray(number)) // false
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```
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#### Converting array to string
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@ -444,6 +448,7 @@ toString:Converts array to string
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```js
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const numbers = [1, 2, 3, 4, 5]
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console.log(numbers.toString()) // 1,2,3,4,5
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const names = ['Asabeneh', 'Mathias', 'Elias', 'Brook']
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console.log(names.toString()) // Asabeneh,Mathias,Elias,Brook
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```
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@ -455,7 +460,9 @@ join:To join the elements of the array, the argument passed in the join method w
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```js
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const numbers = [1, 2, 3, 4, 5]
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console.log(numbers.join()) // 1,2,3,4,5
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const names = ['Asabeneh', 'Mathias', 'Elias', 'Brook']
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console.log(names.join()) // Asabeneh,Mathias,Elias,Brook
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console.log(names.join('')) //AsabenehMathiasEliasBrook
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console.log(names.join(' ')) //Asabeneh Mathias Elias Brook
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@ -575,7 +582,8 @@ reverse: reverse the order of an array
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```js
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const numbers = [1, 2, 3, 4, 5]
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numbers.reverse() // -> reverse array order
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console.log(numbers) // -> [5, 4, 3, 2, 1]
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console.log(numbers) // [5, 4, 3, 2, 1]
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numbers.reverse()
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console.log(numbers) // [1, 2, 3, 4, 5]
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@ -662,11 +670,13 @@ const webTechs = [
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```js
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let text =
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'I love teaching and empowering people. I teach HTML, CSS, JS, React, Python.'
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console.log(words)
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console.log(words.length)
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```
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```sh
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words = ["I", "love", "teaching", "and", "empowering", "people", "I", "teach", "HTML", "CSS", "JS", "React", "Python"]
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console.log(words.length) //13
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["I", "love", "teaching", "and", "empowering", "people", "I", "teach", "HTML", "CSS", "JS", "React", "Python"]
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13
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```
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1. In the following shopping cart add, remove, edit items
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@ -686,6 +696,7 @@ const webTechs = [
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```js
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const frontEnd = ['HTML', 'CSS', 'JS', 'React', 'Redux']
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const backEnd = ['Node','Express', 'MongoDB']
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console.log(fullStack)
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```
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