Extensions of ’sun’ (2)

Write a function @is_sun_extension(s)@ that given an string $s$ , returns True if it is possible to form the word sun by erasing zero or more letters in $s$ and False otherwise. Do not use the index() string method to solve this problem.

Sample session

Problem information

Author: ProAl

Generation: 2026-01-25T16:29:30.626Z