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 = input()

a = input()

b = input()

total = 0

while n > 0:
    if a[n] == 0:
        a[n] = 10
    
    if b[n] == 0:
        b[n] = 10

    d = a[n] - b[n]
    c = b[n] - a[n]

    if c<0:
        c = -1*c

    if d<0:
        d = -1*d

    e = min(c,d)

    total = total + e

    n = n - 1

print(total)            
 				 	  		  	 	 			 			  					