Custom iterator class

Build an iterator that cycles through a list forever, with a stop limit.

iterator class cycle python-basics

Define a class `CyclicIterator` that implements the iterator protocol. The class is initialized with two arguments: `items` (a non-empty list) and `limit` (an integer >= 0). When iterated, it yields elements from `items` cyclically (i.e., after the last element, it goes back to the first) until the total number of yielded elements reaches `limit`. If `limit == 0`, iteration yields nothing. The iterator must raise `StopIteration` naturally when exhausted. Implement the `__iter__` method returning `self`, and `__next__` method that returns the next element or raises `StopIteration` when the limit is reached.

**Function signature:**
```python
class CyclicIterator:
    def __init__(self, items, limit):
        ...
    def __iter__(self):
        ...
    def __next__(self):
        ...
```

Constraints

items is a non-empty list of any hashable? No, just any objects. `limit` is a non-negative integer. The list must not be modified during iteration. Time complexity per `__next__` call is O(1). Maximum `limit` fits within memory.

Example

>>> it = CyclicIterator([1, 2, 3], 3)
>>> list(it)
[1, 2, 3]
>>> it = CyclicIterator(['a', 'b'], 5)
>>> list(it)
['a', 'b', 'a', 'b', 'a']
>>> it = CyclicIterator([True, False], 0)
>>> list(it)
[]

10 points ~15 min

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Hints

Keep track of the current index and the number of elements yielded so far.

When index reaches len(items), reset it to 0.

In __next__, if count >= limit, raise StopIteration.

Remember to return self from __iter__.

Test Results

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