Apply Transform Over Each Element in the Array
Given an integer array arr
and a mapping function fn
, return a new array with a transformation applied to each element.
The returned collection should be created such that returnedArray[i] = fn(arr[i], i)
.
Please solve it without the built-in Array.map
method.
Example 1:
Input: arr = [1,2,3], fn = function plusone(n) { return n + 1; } Output: [2,3,4] Explanation: const newArray = map(arr, plusone); // [2,3,4] The function increases each value in the array by one.
Example 2:
Input: arr = [1,2,3], fn = function plusI(n, i) { return n + i; } Output: [1,3,5] Explanation: The function increases each value by the index it resides in.
Example 3:
Input: arr = [10,20,30], fn = function constant() { return 42; } Output: [42,42,42] Explanation: The function always returns 42.
/**
* @param {number[]} arr
* @param {Function} fn
* @return {number[]}
*/
var map = function(arr, fn) {
for(let i=0; i<arr.length; i++){
arr[i] = fn(arr[i], i);
}
return arr;
};