Given two arrays of integers, compute the pair of values (one value in each array) with the smallest (non-negative) difference. Return the difference.

Example:

Input: {1, 3, 15, 11, 2}, {23, 127, 235, 19, 8}

Output:  3, the pair (11, 8)

Note:

• 1 <= a.length, b.length <= 100000
• -2147483648 <= a[i], b[i] <= 2147483647
• The result is in the range [0, 2147483647]