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())

start=list(input())
end=list(input())

moves=0 

for i in range(n):
    
    #if start is bigger than end 

    if int(start[i])>int(end[i]):
        #go anticlockwise 
        moves_a = int(start[i])-int(end[i])
        #go clock, jump on 9 to 0
        moves_c= (9-int(start[i])) + 1 + (int(end[i])) 

        moves+=min(moves_a,moves_c) 

    elif int(start[i])==int(end[i]):
        moves+=0 
    
    else:

        moves_c= int(end[i]) - int(start[i])
        moves_a= int(start[i]) + 1 + (9-int(end[i])) 

        moves+=min(moves_a, moves_c) 


print(moves)
