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Python Dict vs DefaultDict
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Python Dict vs DefaultDict

EasyPython

Problem

What is the difference between dict and defaultdict?

Explain the difference through a practical frequency-counting function. Implement count_items(items), which accepts a list of strings and returns a regular dictionary mapping each distinct string to its count. Your implementation should demonstrate why defaultdict(int) can simplify counting compared with a standard dict.

Constraints

  • 0 <= len(items) <= 10^4
  • Every item is a string
  • Item strings may repeat
  • Return a regular dictionary

Function Signature

def count_items(items):
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