CF916A Jamie and Alarm Snooze

Jamie loves sleeping. One day, he decides that he needs to wake up at exactly $ hh:mm $ . However, he hates waking up, so he wants to make waking up less painful by setting 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 to press the snooze button. A time is considered lucky if it contains a digit ' $ 7 $ '. For example, $ 13:07 $ and $ 17:27 $ are lucky, while $ 00:48 $ and $ 21:34 $ are not lucky. Note that it is not necessary that the time set for the alarm and the wake-up time are on the same day. It is guaranteed that there is a lucky time Jamie can set so that he can wake at $ hh:mm $ . Formally, find the smallest possible non-negative integer $ y $ such that the time representation of the time $ x·y $ minutes before $ hh:mm $ contains the digit ' $ 7 $ '. Jamie uses 24-hours clock, so after $ 23:59 $ comes $ 00:00 $ .

The first line contains a single integer $ x $ ( $ 1

Print the minimum number of times he needs to press the button.

In the first sample, Jamie needs to wake up at 11:23. So, he can set his alarm at 11:17. He would press the snooze button when the alarm rings at 11:17 and at 11:20. In the second sample, Jamie can set his alarm at exactly at 01:07 which is lucky.