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())
original_state = input()
current_state = input()
sum = 0
dic = {0: -10, 1: -9, 2: -8, 3: -7, 4: -6, 5: -5, 6: -4, 7: -3, 8: -2, 9: -1}
for i in range(len(original_state)):
    forward = abs(int(original_state[i]) - int(current_state[i]))
    if int(original_state[i]) < int(current_state[i]):
         backward = int(original_state[i]) + abs(dic[int(current_state[i])])
    else:
        backward = int(current_state[i]) + abs(dic[int(original_state[i])])
    if forward < backward:
        sum += forward
    else:
        sum += backward
print(sum)