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.
size = int(input())
orgstr = input()
ansstr = input()
org= [int(i) for i in orgstr]
ans = [int(i) for i in ansstr]

c=0
diff=0
for i in range(size):
    if(org[i]>ans[i] and org[i]-ans[i]<=5):
        diff = org[i]-ans[i]
        c=c+diff
    elif(org[i]>ans[i] and org[i]-ans[i]>5):
        diff=(ans[i]+10)-org[i]
        c=c+diff
    elif(ans[i]>org[i] and ans[i]-org[i]<=5):
        diff=ans[i]-org[i]
        c=c+diff
    elif(ans[i]>org[i] and ans[i]-org[i]>5):
        diff=(org[i]+10)-ans[i]
        c=c+diff
print(c)
	 			 	  	 	  			 		  	 		 		 	