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.

#  █████████████████████████████ ██╗  ██╗ █████╗ ██╗     ██████╗  ███████╗ ████████╗ ██╗  ██╗ ████████████████████████████████
#  █████████████████████████████ ██║ ██╔╝██╔══██╗██║     ██╔══██╗ ██╔════╝ ██ ╔════╝ ██║  ██║ ████████████████████████████████
#  █████████████████████████████ █████╔╝ ███████║██║     ██║  ██║ █████╗   ████████║ ███████║ ████████████████████████████████
#  █████████████████████████████ ██╔═██╗ ██╔══██║██║     ██║  ██║ ██╔══╝   ╔════╝██║ ██╔══██║ ████████████████████████████████
#  █████████████████████████████ ██║  ██╗██║  ██║███████╗██████╔╝ ███████╗ ████████║ ██║  ██║ ████████████████████████████████
#  █████████████████████████████ ╚═╝  ╚═╝╚═╝  ╚═╝╚══════╝╚═════╝  ╚══════╝ ╚══════╝╚ ═╝   ╚═╝ ████████████████████████████████

MOD = int(1e9)+7
from math import sqrt,ceil,log2,floor,gcd,pi
from collections import deque
from itertools import permutations
import sys

def solve():
  moves = 0
  for i in range(n):
    if abs(int(original[i])-int(open[i]))>5:
      mx = max(int(original[i]),int(open[i]))
      mn = min(int(original[i]),int(open[i]))
      moves += (9-mx)+1+mn
    else:
      moves += abs(int(original[i])-int(open[i]))

  print(moves)


if __name__=='__main__':
  n = int(input())
  open = input()
  original = input()
  solve()
