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Optimize Data Retrieval
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Optimize Data Retrieval

HardPython

Problem

Write a function to optimize a data retrieval process.

Given a known sequence of item requests and a fixed-size cache, return the minimum number of backend retrievals needed. You may evict cached items, and a request is a cache hit when its item is already stored.

Implement def optimize_data_retrieval(requests, cache_capacity):, returning an integer. Use the optimal offline eviction strategy: when the cache is full, evict the cached item whose next request occurs farthest in the future, or that is never requested again.

Constraints

  • 0 <= len(requests) <= 100000
  • 0 <= cache_capacity <= len(requests)
  • Each request is a non-empty hashable item
  • Return the minimum possible number of backend retrievals

Function Signature

def optimize_data_retrieval(requests, cache_capacity):
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