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+# 2210. Count Hills and Valleys in an Array
+from itertools import groupby
+
+"""
+you are given a 0-indexed integer array 'nums'. an index 'i' is part of a
+hill in 'nums' if the closest non-equal neighbours of 'i' are smaller than
+'nums[i]'. similarly, an index 'i' is part of a valley in 'nums' if the
+closest non-equal neighbours of 'i' are larger than 'nums[i]'. adjacent
+indices 'i' and 'j' are part of the same hill or valley if 'nums[i] ==
+nums[j]'. note that for an index to be part of a hill or valley, it must have
+a non-equal neighbour on both the left and right of the index. return the
+number of hills and valleys in 'nums'.
+"""
+
+
+class Solution(object):
+ def countHillValley(self, nums):
+ """
+ :type nums: List[int]
+ :rtype: int
+ """
+ a = [i for i, _ in groupby(nums)]
+ return sum(l > m < r or l < m > r for l, m, r in zip(a, a[1:], a[2:]))
+
+
+if __name__ == "__main__":
+ obj = Solution()
+ print(obj.countHillValley(nums=[2, 4, 1, 1, 6, 5]))
+ print(obj.countHillValley(nums=[6, 6, 5, 5, 4, 1]))