Least Frequent Letters X67824
Write a function lowfreq(w) that receives a nonempty word made up of lowercase letters and returns all the letters from the word that attain the lowest frequency in it. They should be provided as a single string, and ordered by their standard alphabetical order.
Sample session
>>> lowfreq('madrid') == 'aimr' True >>> lowfreq('sometimes') == 'iot' True >>> lowfreq('badenbaden') == 'abden' True >>> lowfreq('zzzzzz') == 'z' True
Information
- Author
- José Luis Balcázar
- Language
- English
- Official solutions
- Python
- User solutions
- Python