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.
# -----------------------------------------------------------
# URL    : https://codeforces.com/contest/540/problem/A
# Title  : Combination Lock
# Notes  : tag-codeforces, tag-problem-A, tag-div-2
# -----------------------------------------------------------


def solve():
    k = int(input())
    a = list(map(int, list(input())))
    b = list(map(int, list(input())))
    m = 0

    for i in range(k):
        x = min(abs(a[i] - b[i]), 10 - abs(a[i] - b[i]))
        m += x

    print(m)


if __name__ == "__main__":
    solve()
