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())
org = list(map(int,list(input())))
secret = list(map(int,list(input())))
moves = 0
for i in range(n):
    if org[i]==0:
        if secret[i]==0:
            moves += 0
        elif secret[i]<=5:
            moves += secret[i]
        else:
            moves += 10-secret[i]
    elif secret[i]==0:
        if org[i]==0:
            moves += 1
        elif org[i]<=5:
            moves += org[i]
        else:
            moves += 10-org[i]
    elif (org[i])>=6:
        moves += min(abs(org[i]-secret[i]),secret[i]+10-org[i])
    else:
        moves += min(abs(org[i]-secret[i]),org[i]+10-secret[i])
print(moves)