给定两个不含重复元素的序列，从中任意各取一个元素求和，剔 除重复元素，构成一个新的序列（简称为和序列）。求该和序列中自 小到大的第K 个元素。-Given the sequence of two non-repeating elements from each of any one element summation, tick In addition to repeated elements constitute a new sequence (referred to as seq