What does the algorithm output when the user types -1?

The algorithm is designed to respond to specific user inputs. When the user types -1, the algorithm recognizes this input as a trigger to output "Goodbye." This outcome likely stems from the defined behavior within the algorithm, whereby -1 is programmed as a signal for termination or a farewell message. As a result, when this value is input, the algorithm executes the corresponding instruction, which results in displaying "Goodbye" to the user.

In scenarios where other values are input, different responses may be programmed, which is why there are alternative outcomes. However, the specific handling of -1 has been designated to produce the farewell phrase, highlighting how input directly correlates to output based on the established logic within the algorithm. This behavioral mechanism showcases fundamental principles of algorithms and control flow in programming, where specific inputs lead to predetermined responses.