题目要求
An array is monotonic if it is either monotone increasing or monotone decreasing.
An array A is monotone increasing if for all i <= j, A[i] <= A[j]. An array A is monotone decreasing if for all i <= j, A[i] >= A[j].
Return true if and only if the given array A is monotonic.
题目分析及思路
定义了一个monotonic数组，要求它要么是单调递增（对所有索引i <= j，对应元素A[i] <= A[j]）要么是单调递减（对所有索引i <= j，对应元素A[i] >= A[j]）。现在需要判断给定数组是否是monotonic。可以将给定数组与正序排好的数组和逆序排好的数组进行比较，若满足其中一项，则返回True。
python代码
class Solution:
def isMonotonic(self, A: List[int]) -> bool:
return A == sorted(A) or A == sorted(A, reverse=True)