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())
m=input()
d=input()
mylist1=[]
mylist=[]
# for i in range(n-1):
count=0
for j in m:
    mylist.append(int(j))
for k in d:
    mylist1.append(int(k))

for i in range(n-1):
    if abs(mylist[i]-mylist1[i])<6:
        count+=abs(mylist[i]-mylist1[i])
    elif abs(mylist[i] - mylist1[i]) >= 6:
        g=10-abs(mylist[i] - mylist1[i])
        count+=g
    else:
        count += abs(mylist[i] - mylist1[i])
print(count+2)