How to return the index from two array?

Question

I have two array my desired result is to return the index from matching values. How to do that?

For instance I have these two array:

const arr1 = [ monkey, lion, giraffe, bear, ant, fish, dinosaur ]

cosnt arr2 = [ lion, giraffe, bear ]

How to return the result as the index from matching values?

Answer 1

You can try like this.

const arr1 = [ 'monkey', 'lion', 'giraffe', 'bear', 'ant', 'fish', 'dinosaur' ]
const arr2 = [ 'lion', 'giraffe', 'bear' ];
let index = [];

arr2.forEach(function(a,i){
  index.push(arr1.indexOf(a));
});
console.log(index);

//another way using map function
let result = arr2.map((a,i)=>{
   return arr1.indexOf(a);
})
console.log(result);