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Get comfortable with JS arrays: exercises for beginners

Kauress on January 03, 2020

Just a few exercises that I came up with while tutoring. The goal is to wrap your head around iterating over arrays as a pre-cursor to learning the...
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tripol profile image
Ekanem • • Edited

Some quick solutions

5)

let myArr = [ 1, 2, 'One', true];

let newArray = myArr.map(item => `This item is ${item}`)
console.log(newArray)
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6)

let student1Courses = ['Math', 'English', 'Programming'];
let student2Courses = ['Geography', 'Spanish', 'Programming'];

let commonCourse = [...student1Courses, ...student2Courses].reduce((total, item, index, array) => {
  (array.indexOf(item, index + 1) !== -1 && total.indexOf(item) === -1) ? total.push(item) : null
  return total
}, [])

console.log(commonCourse)
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camicode profile image
CamCode • • Edited

Hi @kauresss ,
thanks for these exercises!!!
I completed all and they help me to understand better Array

P.s I don't if it's error or not , but in eighth exercise there are same name variable ( values2)

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Kauress •

You're welcome! And thanks for pointing that out, I've corrected it :)

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des3000 profile image
des3000 •

Hello, can you give link to solutions of this exercises? I don't know if I am doing them correctly

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mahmoudalawad profile image
mahmoud •

Some solutions (6)

let student1Courses = ['Math', 'English', 'Programming', 'd'];
let student2Courses = ['Geography', 'd', 'Spanish', 'Programming'];

const filterArray = student1Courses.filter(value => student2Courses.includes(value));

function filterArray(){
const diff = [];
for (let i = 0; i < student1Courses.length; i++) {
const val1 = student1Courses[i];

  for (let j = 0; j < student2Courses.length; j++) {
      const val2 = student2Courses[j];


  if (val2.includes(val1) ) {

    diff.push(val2);
    console.log(diff);

}
  }

}
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}

filterArray();

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lucarioowns profile image
Roy Frias • • Edited

Hello Kauress I was wondering if you can give us a link to the solutions to the problems please , I want to make sure that I am doing them correctly, if you can be so kind.

sincerely Roy Frias

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kauresss profile image
Kauress •

Hello Roy, sure I'll put up the solutions soon. I'm finishing a 400+ coding exercises workbook after which I'll get some free time

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lucarioowns profile image
Roy Frias •

Ah Ok cool, Thank you so much !!

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brogeby profile image
brogeby •

Solution to 9)

const furniture = ['Table', 'Chairs', 'Couch']
furniture.forEach(e => console.log(e.split('')))
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scarfada profile image
scarfada •

**_

Question 4

_**

var wowDatatypes = ['Scarlaty', 26, true, null, ['Cool']]

wowDatatypes.forEach(differentDataType)

function differentDataType(item, index){
console.log('['+index+']'+ " " +item)
}

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Manaswini Janaswamy •

can you please share solutions

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scarfada profile image
scarfada •

**

Question 3

**

var Planets = ['Vênus', 'Marte', 'Mercúrio','Urano','Jupter','Netuno']
Planets.reverse()

Planets.forEach(Interation)

function Interation(item, index){

console.log('['+index+']', item)
}

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aizenmarina •

Hi Kauress, I really liked these exercises because they are just what I needed to practice (and force myself to find out how to solve them! ) Could you please share more? Many thanks! ;)

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Josh Ivan Lanuevo •

Solution # 3

const Planets = ["mercury", "venus", "earth", "mars", "jupiter"];

Planets.forEach((element,index) => console.log(element,index));

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scarfada profile image
scarfada •

Question 5

let myArr = [ 1, 2, 'One', true];

myArr.filter(passandoPelaArray)

function passandoPelaArray(filtrando){

console.log(filtrando)
}