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Sample code to analyze

Fix & optimize mode – preview

There are no functional bugs in the provided code, but there are areas of improvement in terms of naming conventions and code redundancy. The functions f and f2 have similar logic, which suggests the possibility of merging or improving their design.

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Problem

Fibonacci sequence iterator

Write an iterator class that generates Fibonacci numbers up to a specified maximum value.

Example:

Input: fib = FibonacciIterator(20)
Output: 0, 1, 1, 2, 3, 5, 8, 13

Solution + Detailed explanation

Iterator implementation

The iterator uses class state to store the current values of the sequence. We initialize current = 0 and next_value = 1. In the __next__() method, we check if current > max_value. If so, we raise StopIteration. Otherwise, we return current and update values: current = next_value, next_value = current + next_value. Time complexity is $O(n)$ , where $n$ is the number of generated values.

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