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Data Structures for Performance
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Data Structures for Performance

HardPython

Problem

Inspire11's Delivery Intelligence workspace receives deployment and delivery windows that can be added, cancelled, and queried while a scheduling session is active. Implement an efficient structure that returns the maximum number of overlapping active windows whenever a query is issued.

Each delivery window covers the half-open interval [start, end), so a window ending at time t does not overlap one starting at t.

Formal Specification

Write process_windows(operations). operations is a list where each operation is one of:

  1. ['add', window_id, start, end], adding a window.
  2. ['remove', window_id], removing an existing window.
  3. ['query'], recording the current maximum overlap.

Return a list of integers containing one result for each query, in operation order. Window identifiers are unique while active. All removals are valid.

Constraints

  • 1 <= len(operations) <= 200,000
  • 0 <= start < end <= 1,000,000,000
  • There are at most 100,000 add operations
  • Every window ID is unique while active
  • Every remove operation refers to an active window
  • Intervals use half-open semantics: [start, end)

Function Signature

def process_windows(operations):
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