HackMD2619. Array Prototype Last
tags: leetcode 30 days js challenge Easy
題目描述
Write code that enhances all arrays such that you can call the array.last() method on any array and it will return the last element. If there are no elements in the array, it should return -1.
範例
Example 1:
Input: nums = [1,2,3]
Output: 3
Explanation: Calling nums.last() should return the last element: 3.
Example 2:
Input: nums = []
Output: -1
Explanation: Because there are no elements, return -1.
Constraints:
0 <= arr.length <= 10000 <= arr[i] <= 1000
解答
TypeScript
declare global {
interface Array<T> {
last(): T | -1;
}
}
Array.prototype.last = function() {
return this.length === 0 ? -1 : this[this.length - 1];
};
SheepSat, May 27, 2023
