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.
# i = int(input())
# for i in range(i):
#     vis = {}
#     len_a = int(input())
#     a = input().split(" ")
#     for j in range(len_a):
#         a[j] = abs(int(a[j]))
#         if vis.get(a[j]) is None:
#             vis[a[j]] = 0
#         vis[a[j]] += 1
#         vis[a[j]] = min(vis[a[j]], 2)
#     if vis.get(0) is not None:
#         vis[0] = 1
#     sum = 0
#     for j in vis.keys():
#         sum += vis[j]
#     print(sum)

# 我是分割线
len_disk = int(input())
now_disk = input()
target_disk = input()
min_turn = 0
for i in range(len_disk):
    now_disks = int(now_disk[i])
    target_disks = int(target_disk[i])
    a = 0
    b = 0
    a_now_disk = now_disks
    a_target_disk = target_disks
    b_now_disk = now_disks
    b_target_disk = target_disks
    while a_now_disk != a_target_disk:
        a += 1
        a_now_disk += 1
        a_now_disk %= 10
    while b_now_disk != b_target_disk:
        b += 1
        b_now_disk -= 1
        b_now_disk = (b_now_disk+10)%10
    min_turn += min(a, b)
print(min_turn)

