Level 3Exercise #53
Inventory after sales
Subtract sold quantities from stock and discard zero or negative results.
What you’ll practice
This Level 3 exercise focuses on Counter subtraction in the Collections curriculum. Solve the challenge prompt above using clear, idiomatic Python and the relevant language or standard-library tools.
Relevant Python reference: collections.Counter.
Sample Test Cases
Example #1
Input:
remaining({'pen':4,'book':2}, {'pen':1,'book':3})Output:
Counter({'pen':3})Further Reading
Reference Solution
Reveal Reference Solution
def remaining(stock: dict[str, int], sold: dict[str, int]): from collections import Counter return Counter(stock) - Counter(sold)Pro Tips & Keyboard Shortcuts
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