How to sort an array based off an array of indexes that are in order?-CodePudding

I'm trying to sort an array of words based off an array of indexes. Here is the array of words:

const animalArray = ['Wolf', 'Cat', 'Dog', 'Rabbit', 'Random']

Here is an Array of indexes that i have been given that correlate to the order the animal array above needs to be in:

const indexArray = [ 3, 0, 1, 2 ]

So in indexArray, we start off with index 3. This correlates to 'Rabbit' in the animalsArray. 3 is at index 0 in the indexArray so we should should move 'Rabbit' to index 0. We should keep doing this until we reach the end of the array. Any extras should be added to the end of the array. So once the function runs, we should get the following result:

sortArray(animalArray, indexArray); // ['Rabbit', 'Wolf, 'Cat', 'Dog', 'Random']

I have figured out the first part (create the index array). However, i don't know how to get them in the correct order. How can i put the animalsArray in the correct order?

EDIT:

I oversimplified this and ended up not asking the question correctly.

We should actually pass 3 params to the sortArray, the third being an object that gets sorted:

const animalObjects = [
 { 
  name: 'the Wolf goes to the beach'
 },
 {
  name: 'the Cat climbs a tree'
 },
 {
  name: 'the Dog runs around'
 },
 {
  name: 'the Rabbit burrows'
 },
 {
  name: 'Random extra object that should be at the end'
 }
]

It should sort like so:

sortArray(animalArray, indexArray, animalObjects);

/* returns -

[
 {
  name: 'the Rabbit burrows'
 },
 { 
  name: 'the Wolf goes to the beach'
 },

 {
  name: 'the Cat climbs a tree'
 },
 {
  name: 'the Dog runs around'
 },
 {
  name: 'Random extra object that should be at the end'
 }
]

*/

CodePudding user response：

var sortedAnimalArray =  []

for(var i = 0; i < indexArray.length; i   {
   sortedAnimalArray[i] = animalArray[indexArray[i]]
}

CodePudding user response：

Map the indexArray to access each element at the index, then go through the animals to identify holes.

const animalArray = ['Wolf', 'Cat', 'Dog', 'Rabbit', 'Random'];
const indexArray = [ 3, 0, 1, 2 ];

const indicies = new Set(indexArray);
const results = indexArray
  .map(index => animalArray[index])
  .concat(
    animalArray.filter((_, index) => !indicies.has(index))
  );
console.log(results);

CodePudding user response：

You can use promise .

const myPromise = new Promise((resolve, reject) => {  
const animalArray = ['Wolf', 'Cat', 'Dog', 'Rabbit', 'Random']
const indexArray = [ 3, 0, 1, 2 ] 
let pushArray = []
var resolveValue = 0
 for(var i=0;i<indexArray.length;i  ){
   pushArray.push(animalArray[indexArray[i]])
   resolveValue   
 }
 console.log(pushArray)
if(resolveValue == indexArray.length){
  resolve('Promise is resolved successfully.');  
  }
});

CodePudding user response：

To make it simple.

Use Array.map() to iterate the indexArray
Compare the elements in both the array using Array.indexOf() and push the remaining element into a result array.

Try this :

const animalArray = ['Wolf', 'Cat', 'Dog', 'Rabbit', 'Random'];
const indexArray = [ 3, 0, 1, 2 ];

const newArray = indexArray.map((item) => animalArray[item]);

animalArray.forEach((animal) => {
    if (newArray.indexOf(animal) === -1) {
    newArray.push(animal)
  }
})

console.log(newArray);