Wake Up Sid

Sid is a student who loves sleeping so much.But, at the time of exams he has to wake up exactly at hh:mm. However, he hates waking up early. So, to decrease the frustration of waking up early, he sets the alarm at a lucky time. He will then press the snooze button every x minutes until hh:mm is reached, and only then he will wake up. He wants to know what is the smallest number of times he needs t