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.
n = int(input())
current = input()
desired = input()
sum_ = 0
for i in range(n):
    c = int(current[i])
    d = int(desired[i])
#     print(c,d)
    direct_dist = abs(c-d)
    
    if c < d:
        c = c + 10
    else:
        d = d + 10
    
    indirect_dist = abs(c-d)
        
    if direct_dist < indirect_dist:
        sum_ = sum_ + direct_dist
#         print(direct_dist,"d")
    else:
        sum_ = sum_ + indirect_dist
#         print(direct_dist,"i")

    
        
print(sum_)