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2635. Apply Transform Over Each Element in Array
tags: leetcode 30 days js challenge Easy
2635. Apply Transform Over Each Element in Array
題目描述
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.
範例
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.
Constraints:
0 <= arr.length <= 1000- -109 <=
arr[i]<= 109 fn returns a number
解答
TypeScript
function map(arr: number[], fn: (n: number, i: number) => number): number[] {
const result = [];
for (let i = 0; i < arr.length; i++) {
result.push(fn(arr[i], i));
}
return result;
}
SheepMon, May 8, 2023
