Scrooge McDuck keeps his most treasured savings in a home safe with a combination lock. Each time he wants to put there the treasures that he's earned fair and square, he has to open the lock.

The combination lock is represented by *n* rotating disks with digits from 0 to 9 written on them. Scrooge McDuck has to turn some disks so that the combination of digits on the disks forms a secret combination. In one move, he can rotate one disk one digit forwards or backwards. In particular, in one move he can go from digit 0 to digit 9 and vice versa. What minimum number of actions does he need for that?
The first line contains a single integer *n* (1 ≤ *n* ≤ 1000) — the number of disks on the combination lock.

The second line contains a string of *n* digits — the original state of the disks.

The third line contains a string of *n* digits — Scrooge McDuck's combination that opens the lock.
n = int(input())
x = input()
y = input()
a = list(x)
b = list(y)

l = []
for i in a:
	l.append(int(i))

m = []
for i in b:
	m.append(int(i))

total = 0
for i in range(n):
	d = l[i] - m[i]
	if d >= 6:
		total += (10+m[i]) - l[i]
	elif d <= -6:
		total += (10+l[i]) - m[i]
	elif l[i] > m[i]:
		total += l[i] - m[i]
	else:
		total += m[i] - l[i]

print(total)