Remove Duplicate Integers While Preserving Order

Question

This question asks the candidate to write a function that removes duplicate integers from a list while preserving the original order of the elements.

Codemia · Accepted Answer

To solve the problem of removing duplicate integers while preserving order, I will use a set to track seen integers and a list to store the result. This allows me to efficiently check for duplicates and maintain the order of first appearances.

1. Initialize an empty set called `seen` and an empty list called `result`.
2. Iterate through each integer in the input list:
   - If the integer is not in `seen`, add it to both `seen` and `result`.
3. Return the `result` list as the output.

The time complexity of this solution is O(n), where n is the number of integers in the input list, since we are making a single pass through the list. The space complexity is also O(n) in the worst case, where all integers are unique.

```python
def remove_duplicates(nums):
    seen = set()
    result = []
    for num in nums:
        if num not in seen:
            seen.add(num)
            result.append(num)
    return result

# Example usage:
print(remove_duplicates([1, 2, 2, 3, 4, 4, 5]))  # Output: [1, 2, 3, 4, 5]
```

It's important to handle edge cases, such as an empty list, which should simply return an empty list. Additionally, if all elements are duplicates, the output should only contain the first occurrence.

Remove Duplicate Integers While Preserving Order

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