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())
f1=input()
f2=input()
sum=0
for i in range(n):
    if f1[i]!=f2[i]:
        count1=0
        count2=0
        copy=int(f1[i])
        while 1:
            copy += 1
            count1 += 1
            if copy>9:
                copy=0
            if copy == int(f2[i]):
                break
        copy=int(f1[i])
        while 1:
            copy -= 1
            count2 += 1
            if copy<0:
                copy=9
            if copy == int(f2[i]):
                break
    if count1<count2:
        sum += count1
    else:
        sum += count2
print(sum)