Definition: Prederiving is a concept in computer science where a program or algorithm can be executed multiple times without changing its output, only by modifying its state. This means that the input to the program remains unchanged but the program outputs something different each time it runs. For example, consider a simple arithmetic expression evaluator. The function `evaluate` takes two operands and an operator as inputs and returns their result. If the operator is addition (`+`) or subtraction (`-`), the function checks if both operands
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