public class Solution
extends Object
862 - Shortest Subarray with Sum at Least K\.
Hard
Given an integer array `nums` and an integer `k`, return _the length of the shortest non-empty **subarray** of_ `nums` _with a sum of at least_ `k`. If there is no such **subarray** , return `-1`.
A **subarray** is a **contiguous** part of an array.
**Example 1:**
**Input:** nums = [1], k = 1
**Output:** 1
**Example 2:**
**Input:** nums = [1,2], k = 4
**Output:** -1
**Example 3:**
**Input:** nums = [2,-1,2], k = 3
**Output:** 3
**Constraints:**
* 1 <= nums.length <= 105
* -105 <= nums[i] <= 105
* 1 <= k <= 109