Sequential Unwind

Definition

Sequential Unwind in plain English

Use Sequential Unwind when a process runs forward with a clear inverse (undo last operation first). Clues include work backward, after the last step, originally, or reverse the operations. Invert each step from the end to the start; keep types (integer, positive) in view so an illegal undo is rejected immediately. Forward guessing fights the terminal constraint; unwinding meets the known end-state first and walks home. If an operation is not invertible uniquely, stop and switch to cases. Micro-example: a number is doubled, then 3 is added, ending at 17. Undo add-3 to get 14, then halve to get 7. That original 7 is faster than guessing forward candidates that might end at 17.

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