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())
fir = input()
sec = input()
ans = 0
x = 0

while n > 0:
    
    firr = int(fir[x])
    secc = int(sec[x])

    if abs(firr - secc) <= 5:
        ans = ans + abs(firr - secc)
        
    else:
        if firr < secc:
            ans = abs(9 - secc + firr) + 1
        if secc > firr:
            ans = abs(9 - firr + secc) + 1
        
    n -= 1
    x += 1
    
print(ans)

    