How should I practice Count Valleys in a Wiggle Pattern?

Start by reading the full statement, solve the visible examples, then compare the pattern against related CoinDCX phone screen problems in FastPrep.

Is Count Valleys in a Wiggle Pattern associated with CoinDCX?

FastPrep tags this as a CoinDCX phone screen coding practice problem when the problem catalog has that company and stage context.

CoinDCX● EasyFULLTIMEPHONE SCREEN

A valley is an interior index whose value is strictly smaller than both adjacent values.

Return the number of valleys in nums. Endpoints are never valleys, and equal neighbors do not form a strict valley.

countValleys(nums: int[]) → int

nums = [5,1,4,2,3]return = 2

Indices 1 and 3 are strict valleys.

nums = [1,2,3]return = 0

The sequence has no valley.

Source note: Author-written prompt excerpt retained for source fidelity.