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.
import sys
sys.setrecursionlimit(100000000)
input=lambda:sys.stdin.readline().strip()
write=lambda x:sys.stdout.write(str(x)+'\n')

# from random import randint
# from copy import deepcopy
# from collections import deque
# from heapq import heapify,heappush,heappop
# from bisect import bisect_left,bisect,insort
# from math import inf,sqrt,gcd,ceil,floor,log,log2,log10,pi
# from functools import cmp_to_key


n=int(input())
s=input()
t=input()
ans=0
for i in range(n):
    x=abs(int(s[i])-int(t[i]))
    ans+=min(x,10-x)
print(ans)