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Validate & Normalize Phone Numbers

intermediate~12 min25 pts
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Problem

Given a list of phone-number strings in various formats, return a dict with two keys:

  • valid: sorted list of unique normalized numbers (digits only, exactly 10 digits)
  • invalid: sorted list of the original (unmodified) strings that couldn't be normalized to exactly 10 digits

Acceptable input shapes include: (415) 555-0100, 415.555.0100, 415-555-0100, +1 415 555 0100, 4155550100. Leading +1 or 1 country code is allowed and should be stripped.

RegexreValidationNormalization
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Python Editor

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Topfolio

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