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=input()
s2=input()
cnt=0
for i in range (n):
    a=int(s1[i])
    b=int(s2[i])
    if a==b: continue
    elif a>b:
        x=(a-b)
        y=(9-a)+b+1
        if x>=y:
            cnt+=y
        else:
            cnt+=x
    elif a<b:
        x=(b-a)
        y = (9 - b) + a+1
        if x >= y:
            cnt += y
        else:
            cnt += x
print(cnt)

 				   		 			  				   	  	 		