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.
def distance(num1, num2):
    if (num1 >= 5 and num2 >= 5):
        return abs(num1-num2)
    elif (num1 < 5 and num2 < 5):
        return abs(num1 - num2)
    else:
        if (abs(num1 - num2) < 5):
            return abs(num1 - num2)
        elif (num1 >= 5):
            return 10-num1 + num2
        else:
            return 10-num2 + num1

count = int(input())
init = int(input())
password = int(input())

moves = 0
for i in range(count):
    dig1 = init % 10
    dig2 = password % 10

    moves+= distance(dig1,dig2)

    init//=10
    password//=10

print(moves)