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.
Following are our arrays −
const arr1 = [34, 78, 89]; const arr2 = [78, 67, 34, 99, 56, 89];
Let's write the code and check for multiple values −
Example
const arr1 = [34, 78, 89]; const arr2 = [78, 67, 34, 99, 56, 89]; const contains = (first, second) => { const indexArray = first.map(el => { return second.indexOf(el); }); return indexArray.indexOf(-1) === -1; } console.log(contains(arr1, arr2));
Output
The output in the console will be −
true