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())
a=list(map(int,input()))
b=list(map(int,input()))
y=0
for i in range(n):
    while a[i]!=b[i]:
        x=a[i]-b[i]
        if x<=5 and x>0:
            y=y+1
            a[i]=a[i]-1
        if abs(x)<=5 and x<0:
            y=y+1
            a[i]=a[i]+1
        if x>5 and x>0:
            y=y+1
            a[i]=a[i]+1
            if a[i]>9:
                a[i]=0
        if abs(x)>5 and x<0:
            y=y+1
            a[i]=(a[i]-1)
            if a[i]<0:
                a[i]=9
        #print(a[i],b[i])
print(y)