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())
a =list(map(int ,input()))
b =list(map(int, input()))

res =0
for i in range(n):
    if a[i] > b[i]:
        if a[i] - b[i] < 5:
            res+= a[i] - b[i]

        elif a[i] - b[i] >=5:
            while a[i] != 9:
                res+=1
                a[i] +=1
            if a[i] == 9:
                res+=1
                c = b[i]
                res+=c
    elif b[i] >a[i]:
        if b[i] - a[i] <5:
            res+= b[i] - a[i]

        elif b[i] -a[i] >=5:
            while b[i] != 9:
                res+=1
                b[i] +=1
            if b[i] == 9:
                res+=1
                c =a[i]
                res+=c
    else:
        res+=0
print(res)