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.
a=int(input())
b=list(map(int,input()))
c=list(map(int,input()))
k=0
p=[]
for x in range(len(b)):
    v=max(b[x],c[x])-min(b[x],c[x])
    if v<5:
        k+=v
    else:
        if b[x]==0:
            b[x]=0
            k+=1
        else:
            if b[x]==9:
                b[x]=0
                k+=1
                while b[x]!=c[x]:
                    b[x]+=1
                    k+=1
            else:
                if b[x]==1 and c[x]!=0:
                    b[x]=9
                    k+=2
                    while b[x]!=c[x]:
                        b[x]-=1
                        k+=1
                elif b[x]==2 or b[x]==3 or b[x]==4:
                    while b[x]!=0:
                        b[x]-=1
                        k+=1
                    b[x]=9
                    k+=1
                    while b[x]!=c[x]:
                        b[x]-=1
                        k+=1
                elif b[x]==1 and c[x]==0:
                    b[x]=0
                    k+=1
print(k)
                