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 = input()
state = input()
goal = input()
steps = 0
for i in range(int(n)):
	s = ord(state[i])-48
	g = ord(goal[i])-48
	if(g>s):
		up = g-s
		down = (s+1)+(9-g)
		steps += min(up,down)
	elif (s>g):
		down = s-g
		up = (9-s)+1+(g-0)
		steps+=min(up,down)

print(steps)