Solution

Method 1 - Using Priority Queue

The problem requires determining the earliest building (in terms of index) that both Alice and Bob can move to based on their starting positions and the respective heights of the buildings. To solve this efficiently, we leverage a combination of preprocessing, deferred processing, and a priority queue (min-heap):

Immediate Resolution: For some queries, we can immediately decide the result based on the initial heights and positions of Alice and Bob.
Deferred Processing: For queries that cannot be immediately resolved, we store them for later processing when exploring future buildings.
Deferred Query Handling: When processing buildings in order, we use a priority queue to efficiently determine if there are any deferred queries that can now be resolved.

Approach

Preprocessing of Queries:
- For each query where Alice and Bob start at the same building, they can meet at that building.
- For queries where Alice's building height is less than Bob's and Alice's index is less than Bob's, Alice can move directly to Bob's building.

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