#149EasyErrors & Exceptions· try / except

Safe Integer Parser

A program reads numbers that people typed, one per line, and some lines are bad. It should add up what it can and report the rest instead of crashing. Write `parse_numbers(items)` that tries to convert each string with `int()`: - Successful values are added to a running total. - For each failure, record the message `item <position>: "<text>" is not a whole number`, where the position counts from 1 and `<text>` is the original string. Return `{"total": <sum>, "errors": [<messages in order>]}`. Surrounding spaces and a leading `+` or `-` are fine, because `int()` accepts them.

Input format

`items`: a list of strings. Test data only uses ASCII characters and no underscores.

Output format

A dictionary with keys `total` and `errors`.

Examples

Input: items = ["10"," -3 ","abc","4.5"]

Output: {"total":7,"errors":["item 3: \"abc\" is not a whole number","item 4: \"4.5\" is not a whole number"]}

10 and -3 convert. `abc` and `4.5` raise `ValueError` in `int()`.

Input: items = []

Output: {"total":0,"errors":[]}

Nothing to add and nothing to report.

Constraints

0 <= len(items) <= 10^4

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Errors and Exceptions in Python

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