Pointers, Allocation, Leaks | Dataford Interview Questions

What are pointers, dynamic allocation, and memory leaks?

Implement a function that models dynamic memory ownership by processing allocation and release events. Return the identifiers of blocks that remain allocated, preserving their allocation order.

Input and Output

events is a list of ['alloc', id] or ['free', id] pairs. Return a list of allocated identifiers that were never freed.

Constraints

1 <= len(events) <= 10000
Each event is a two-element list containing an operation and an integer block identifier
Operations are either 'alloc' or 'free'
Each block is allocated at most once and freed only after it is allocated
Block identifiers are unique integers

Function Signature

def find_memory_leaks(events):

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Problem