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Stack Aggregation With Monthly Diffs
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Stack Aggregation With Monthly Diffs

MediumPython

Problem

Solve a stack aggregation problem where you get just the diff for each month and need to efficiently keep track. Implement aggregate_stack_diffs(monthly_ops), where each month contains stack operations of the form ["push", value] or ["pop"]. Return the stack sum and maximum value after each month, using null for the maximum when the stack is empty.

Input is a list of monthly operation lists. Each pop is valid, and values are integers.

Constraints

  • 1 <= len(monthly_ops) <= 10^4
  • 0 <= total number of operations <= 10^5
  • Each operation is either ['push', value] or ['pop']
  • -10^9 <= value <= 10^9
  • Every pop operation is valid for the current stack

Function Signature

def aggregate_stack_diffs(monthly_ops):
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