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 = {}
    a = input().split("")
    len_a = int(input())
    for j in range(len_a):
        a[j] = 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)