JavaScript Array: Checking for multiple values

We are required to write a JavaScript function that takes in two arrays of Numbers and checks whether all the elements of the first array exist in the second or not.

Example

The code for this will be −

const arr1 = [34, 78, 89];
const arr2 = [78, 67, 34, 99, 56, 89];
const multipleIncludes = (first, second) => {
   const indexArray = first.map(el => {
      return second.indexOf(el);
   });
   return indexArray.indexOf(-1) === -1;
}
console.log(multipleIncludes(arr1, arr2));

Output

The output in the console −

true