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.
x=int(input())
b=[str(i) for i in input().split()]
# print(b)
hh=b[0]	
mm=b[1]
if hh[0]=="0":
	hh=hh[1:]
	hh=int(hh)
if mm[0]=="0":
	mm=mm[1:]
	mm=int(mm)

# print(hh,mm)

nh=hh
nm=mm
f=0
y=0
cnt=0
need=60/x
while(f==0):
	nh=str(nh)
	nm=str(nm)	
	if '7' in nh or '7' in nm:
		f=1
		break
	nh=int(nh)
	nm=int(nm)
	if x>nm:
		d= x-nm
		if nh==0:
			nh=23
		else:
			nh-=1
		nm= 60-d
	else:
		nm-=x
	y+=1
	# print(y)

if f==1:
	print(y)
# else:
# 	if 8<=nh<=16:
# 		y+= need*(nh-8)
# 		nh=8
# 	elif 0<=y<=6:
# 		y+= need*(nh+5)
# 		nh=18
# 	else:
# 		y+=need*(nh-18)

# while(f==0 and y<need):
# 	nh=str(nh)
# 	nm=str(nm)	
# 	if '7' in nh or '7' in nm:
# 		f=1
# 		break
# 	nh=int(nh)
# 	nm=int(nm)
# 	if x>nm:
# 		d= x-nm
# 		if nm==0:
# 			nm=23
# 		else:
# 			nm-=1
# 		nm= 60-d
# 	else:
# 		nm-=x
# 	y+=1
# 	# print(y)

# if f==1:
# 	print(y)














'''


'''
	