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.

Input

The first line contains a single integer x (1 ≤ x ≤ 60).

The second line contains two two-digit integers, hh and mm (00 ≤ hh ≤ 23, 00 ≤ mm ≤ 59).

Output

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

Examples

Input

3
11 23


Output

2


Input

5
01 07


Output

0

Note

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.
step = int(raw_input())
hour, minute = map(int,raw_input().split())
#print hour, minute

def get_minute(hour,minute):
    while hour<0:
       hour+=24
    return 60*hour+minute
def get_hour_minute(time_min):
    hour =  time_min/60
    hour = hour%24
    minute = time_min%60
    return str(hour)+str(minute)
def solution(step, hour, minute):
    res = 0
    if (str(hour)+str(minute)).count('7')!=0:
        return res

    time_min = get_minute(hour,minute)
    while True:
        time_min-=step
 
#       print time_min
        res+=1
        while time_min<0:
            time_min+=24*60
        str_time =get_hour_minute(time_min)
#        print 'str_time', str_time
        if str_time.count('7')!=0:
           return res

print solution(step, hour, minute)
