Phone Number Matching With Maps | Dataford Interview Questions

How would you solve a phone number matching problem using a hash map approach?

Write a function that receives two lists, contacts and queries, and returns the matching contact names for each query phone number. Each contact is a pair [name, phone_number], and each query is a phone number string. If a query has no match, return None for that position.

Function

def match_phone_numbers(contacts, queries):

Output

Return a list of names or None values in the same order as queries.

Constraints

1 <= len(contacts), len(queries) <= 10^5
Phone numbers are strings and may contain leading zeros
Contact names are unique
A phone number appears at most once in contacts

Function Signature

def match_phone_numbers(contacts, queries):

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Problem