Return the length of the shortest, non-empty, contiguoussubarray of A with sum at least K.
If there is no non-empty subarray with sum at least K, return -1.
Example 1:
Input: A = [1], K = 1
Output: 1
Example 2:
Input: A = [1,2], K = 4
Output: -1
Example 3:
Input: A = [2,-1,2], K = 3
Output: 3
Note:
- 1 <= A.length <= 50000
- -10 ^ 5<= A[i] <= 10 ^ 5
- 1 <= K <= 10 ^ 9
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