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())
s1 = int(input())
s2 = int(input())
result = 0
# i = 0
while (s1 > 0 or s2 > 0):
    num1 = s1 % 10
    num2 = s2 % 10
    # print("ITER", num1, num2, abs(num2 - num1), abs(9 + num2 - num1), abs(num1 - num2) , result)
    # result += min(abs(num2 - num1), abs(9 + num2 - num1), abs(num1 - num2))
    # print(i, "ITER", num1, num2, abs(num2 - num1), abs(10 + min(num1, num2) - max(num2, num1)), min(abs(num2 - num1), abs(10 + min(num1, num2) - max(num2, num1))))
    result += min(abs(num2 - num1), abs(10 + min(num1, num2) - max(num2, num1)))
    s1 //= 10
    s2 //= 10
    # i += 1
print(result)