In 2025, a curious fashion took hold among adolescents in the Anglophone world: whenever they encountered a 6 occurring somewhere before a 7, they would, with great and rather unearned ceremony, announce “six seven.” Now that the phenomenon has been consigned to oblivion with an almost defensive eagerness by its former adherents, your task is to automate this behaviour, the underlying purpose of which continues to elude scholarly interpretation.

Input

The input consists of:

• One line with a sequence of length () of decimal digits –.

Output

If the line contains a before a , write “six seven”. Otherwise, write “no”.