出處 : https://leetcode.com/problems/find-subsequence-of-length-k-with-the-largest-sum/submissions/
You are given an integer array nums and an integer k. You want to find a subsequence of nums of length k that has the largest sum.
Return any such subsequence as an integer array of length k.
A subsequence is an array that can be derived from another array by deleting some or no elements without changing the order of the remaining elements.
Example 1:
Input: nums = [2,1,3,3], k = 2 Output: [3,3] Explanation: The subsequence has the largest sum of 3 + 3 = 6.
Example 2:
Input: nums = [-1,-2,3,4], k = 3 Output: [-1,3,4] Explanation: The subsequence has the largest sum of -1 + 3 + 4 = 6.
Example 3:
Input: nums = [3,4,3,3], k = 2 Output: [3,4] Explanation: The subsequence has the largest sum of 3 + 4 = 7. Another possible subsequence is [4, 3].
Constraints:
1 <= nums.length <= 1000-105 <= nums[i] <= 1051 <= k <= nums.length
找最大的三個數字，但出現的順序不能變:
/**
* @param {number[]} nums
* @param {number} k
* @return {number[]}
*/
var maxSubsequence = function(nums, k) {
// 先排除 k 等於 nums.length 的情形
if (k === nums.length) return nums
// 用前 k 個當啜預設的結果進 loop
const res = nums.slice(0, k)
for (let i = k; i < nums.length; i++) {
let min = Infinity
let targetIdx = null
// 一直比較前 k 的大小，如果有比之前的數字大，就移除就數字，補新數字。
for (let j = 0; j < k; j++) {
if (res[j] < min) {
min = res[j]
targetIdx = j
}
}
if (nums[i] > min) {
res.splice(targetIdx, 1)
res.push(nums[i])
}
}
return res
};
