8. Flatten
flatten()Asked in screens shaped like: Amazon, Netflix
Flatten a nested list of numbers one level: [[1,2],[3]] → [1,2,3].
Examples
Example 1
Input: { "rows": [[1, 2], [3]] } Output: [1, 2, 3]
Constraints
- Each inner list contains numbers
Implement flatten(). Types below are the NumPy contract; Python and PyTorch use lists or tensors with the same names.
| Name | Type | I/O |
|---|---|---|
| rows | list | Input |
| value | list | Output |
Same tests, three APIs. Pick a language with the chips above the editor.
NumPy
Vectorized arrays. Default for analyst, scientist, and DE screens.
Revealed one at a time. The reference implementation stays in the Solution tab.
Hint 1
Keep the function signature. Fill the body — do not rename parameters.
Hint 2
Match the rounding in the examples. Tests compare with a small numeric tolerance.
Hint 3
Switch NumPy / Python / PyTorch with the chips above the editor. Each language has its own tests.
Run your code to see stdout.
Submit to run the checks.
All tests passed on this language.
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