2635-Apply-Transform-Over-Each-Element-in-Array

2635. Apply Transform Over Each Element in Array

Easy

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Given an integer array arr and a mapping function fn, return a new array with a transformation applied to each element.

The returned array should be created such that returnedArray[i] = fn(arr[i], i).

Please solve it without the built-in Array.map method.

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Example 1:

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.

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Example 2:

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.

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Example 3:

arr = [10,20,30], 
fn = function constant() {
    return 42; 
}
// Output: [42,42,42]

Explanation:
The function always returns 42.

Constraints:

• 0 <= arr.length <= 1000
• 109 <= arr[i] <= 109
• fn returns an integer.

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