Count House Segments After Destruction

You are monitoring building density in a district of houses. The district is represented as a number line, and each house is located at an integer position.
You are given houses, an array containing the initial locations of all houses, and queries, an array containing the locations of houses destroyed in order. After each destroyed house, return the number of house segments remaining.
A house segment is one or more adjacent houses whose positions are consecutive integers and which do not have neighboring houses immediately outside the segment.

Function
countHouseSegmentsAfterDestruction(houses: int[], queries: int[]) → int[]

Examples
Example 1
houses = [1, 2, 3, 6, 7, 9]
queries = [6, 3, 7, 2, 9, 1]
return = [3, 3, 2, 2, 1, 0]
Initially the house segments are [1, 2, 3], [6, 7], and [9]. Removing the houses in query order leaves 3, 3, 2, 2, 1, and then 0 segments.
Example 2
houses = [2, 4, 5, 6, 7]
queries = [5, 6, 2]
return = [3, 3, 2]
After removing 5, the segments are [2], [4], and [6, 7]. After removing 6, the segments are [2], [4], and [7]. After removing 2, two segments remain.

Constraints
All values in houses are distinct.
Every value in queries appears in houses, and all values in queries are distinct.

Keep a hash set of the houses still standing and a running segment count. Start by counting segments: a house starts one if house-1 isn't in the set. For each query x, check whether x-1 and x+1 are present. Both present: removing x splits one segment into two, so count goes up by 1. Neither present: x was a lone segment, so count goes down by 1. Exactly one present: the segment just shrinks, count unchanged. Append the count after each query. That's O(n + q) total. The first-attempt mistake is recounting from scratch per query, which is O(n*q), or forgetting to delete x from the set before the next query. Another slip is mixing up the split case with the shrink case. Check example 2: removing 5 from [4,5,6,7] splits it, giving 3. StealthCoder is your hedge if the case table slips under pressure in the live OA.

Drill it cold or hedge it with StealthCoder. Either way, don't walk into the OA hoping you remember the trick.