Filter_Elements_From_Array.js

/**
 * @param {number[]} arr
 * @param {Function} fn
 * @return {number[]}
 */
var filter = function(arr, fn) {
    const ans =[] ;
    for (const i in arr)
    {
        if(fn(arr[i],Number(i)))
        {
            ans.push(arr[i]);
        }
    }
    return ans;
};