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())

str1 = input()
str2  = input()

num = 0
for i,j in zip(str1,str2):
    i = int(i)
    j = int(j)
    if abs(i-j) <=4:
        num = num  + abs(i-j)
    else:
        if( i < j):
            num = num + abs(9 - j) + i + 1
        else:
            num = num + abs(9-i) + j + 1
print(num)
    
    

