There's a roster of unique names, and we created a dictionary of first name to list of last names. For example, the roster Alice Chan Bob Smith Fred Agarwal Alice Smith
We've created this dictionary mapping first name to a list of associated last names, but dumped the original roster unfortunately:
{'Alice': ['Chan', 'Smith'], 'Bob': ['Smith'], 'Fred': ['Agarwal']}
But now, we want to search by last name. So given only the above dictionary, return a new dictionary where the key is last name instead of first name.
{'Smith': ['Alice', 'Bob'], 'Chan': ['Alice'], 'Agarwal': ['Fred']}
A Few Notes:
1. The order of the lists of first names is ambiguous, but return it sorted alphabetically from A-Z. That means, 'Smith' should map to ['Alice', 'Bob'], NOT ['Bob', 'Alice'].
2. Even if there's only one person with that last name, make sure it's mapped to a list. That means, 'Agarwal' should map to ['Fred'], NOT 'Fred'.
3. Recall dictionaries (and sets) are unordered, so don't be alarmed if the print statement didn't have the last names in the same order as above. BUT, for each last name, the list of first names associated must be sorted.
4. We've assumed the original roster had unique names, so there aren't any issues with that.
1 def reverse_roster (fn_dict:dict) -> dict:
2 # TODO: Your code here (-10-20 lines of code)
3
4 if __name__ == '__main__':
5 sample = {'Alice': ['Smith', 'Chan'], 'Bob': ['Smith'], 'Fred': ['Agarwal']}
6 print (reverse_roster (sample))
7