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())
current = input()
needed = input()
ctr = 0
for i in range(n):
    if int(current[i]) >= int(needed[i]):
        up = int(current[i])-int(needed[i])
    else:
        up = (10+int(current[i]))-int(needed[i])
    if int(current[i]) <= int(needed[i]):
        down = int(needed[i])-int(current[i])
    else:
        down = (10+int(needed[i])-int(current[i])) 
    if up <= down:
        ctr += up
    else:
        ctr +=down 
print(ctr)    