Types: n: int, a: List[int], m: int, b: List[int]  
Ranges: 1 ≤ n, m ≤ 200,000, 0 ≤ a[0] < a[1] < ... < a[n-1] ≤ 10^9, 0 ≤ b[0] < b[1] < ... < b[m-1] ≤ 10^9  
Addtl Info: Elements in `A` and `B` are given in ascending order with no duplicates in each set.