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())
Str = input()
Str1 = input()
Count = 0
for i in range(N):
    N1 = int(Str[i])
    N2 = int(Str1[i])
    
    Minn = min(N1,N2)
    Maxx = max(N1,N2)
    
    Val = Maxx - Minn
    Val1= ( 9 - Maxx) + ( Minn - 0)
    
    if Val <= Val1:
        Count = Count + Val 
    else:
        Count = Count + Val1 + 1
print(Count)