Given two sorted 0-indexed integer arrays `nums1` and `nums2` as well as an integer `k`, return the `kth` (1-based) smallest product of `nums1[i] * nums2[j]` where `0 <= i < nums1.length` and `0 <= j < nums2.length`.

Example 1:

    Input: nums1 = [2,5], nums2 = [3,4], k = 2
    Output: 8
    Explanation: The 2 smallest products are:
    - nums1[0] * nums2[0] = 2 * 3 = 6
    - nums1[0] * nums2[1] = 2 * 4 = 8
    The 2nd smallest product is 8.

Example 2:

    Input: nums1 = [-4,-2,0,3], nums2 = [2,4], k = 6
    Output: 0
    Explanation: The 6 smallest products are:
    - nums1[0] * nums2[1] = (-4) * 4 = -16
    - nums1[0] * nums2[0] = (-4) * 2 = -8
    - nums1[1] * nums2[1] = (-2) * 4 = -8
    - nums1[1] * nums2[0] = (-2) * 2 = -4
    - nums1[2] * nums2[0] = 0 * 2 = 0
    - nums1[2] * nums2[1] = 0 * 4 = 0
    The 6th smallest product is 0.

Example 3:

    Input: nums1 = [-2,-1,0,1,2], nums2 = [-3,-1,2,4,5], k = 3
    Output: -6
    Explanation: The 3 smallest products are:
    - nums1[0] * nums2[4] = (-2) * 5 = -10
    - nums1[0] * nums2[3] = (-2) * 4 = -8
    - nums1[4] * nums2[0] = 2 * (-3) = -6
    The 3rd smallest product is -6.

Constraints:

- `1 <= nums1.length, nums2.length <= 5 * 104`
- `-105 <= nums1[i], nums2[j] <= 105`
- `1 <= k <= nums1.length * nums2.length`
- `nums1` and `nums2` are sorted.