maximum-size-subarray-sum-equals-k.js

/*
 Given an array nums and a target value k, find the maximum length of a subarray that sums to k.
 If there isn't one, return 0 instead.

 Example 1:
 Given nums = [1, -1, 5, -2, 3], k = 3,
 return 4. (because the subarray [1, -1, 5, -2] sums to 3 and is the longest)

 Example 2:
 Given nums = [-2, -1, 2, 1], k = 1,
 return 2. (because the subarray [-1, 2] sums to 1 and is the longest)

 Follow Up:
 Can you do it in O(n) time?
 */