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())

cs = [*input()]
pw = [*input()]

count = 0

for i in range(n) :
    
    if (cs[i] == "0" and pw[i] == "9") or (cs[i] == "9" and pw[i] == "0") :
        count += 1
    
    
    st = abs(int(cs[i]) - int(pw[i]))
    do1 = abs(int(cs[i]) + abs(int(pw[i]) - 10))
    do2 = abs(int(pw[i]) + abs(int(cs[i]) - 10))
    count += min(st, do1, do2)
    


print(count)



			 			  		  		 		   					 	 		