给定一个整数序列，返回其最长摆动子序列的长度。

Given a sequence of integers, return the length of the longest subsequence that is a wiggle sequence.

youdao

给定一个整数序列，返回其最长摆动子序列的长度。

Given a sequence of integers, return the length of the longest subsequence that is a wiggle sequence.

youdao