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.
disks = int(input())

lock = input()
unlock = input()

moves = 0

for i in range(disks):
    temp = 0
    temp2 = 0
    if (int(lock[i]) > int(unlock[i])):
        if (unlock[i] == "1"):
            temp2 = int(unlock[i] + "0")
            temp = int(lock[i])
        elif (unlock[i] == "0"):
            temp2 = int("1" + unlock[i])
            temp = int(lock[i])
        else:
            temp2 = int("1" + unlock[i])
            temp = int(lock[i])
    elif (int(lock[i]) < int(unlock[i])):
        if (lock[i] == "1"):
            temp2 = int(lock[i] + "0")
            temp = int(unlock[i])
        elif (lock[i] != "0"):
            temp2 = int("1" + lock[i])
        else:
            temp2 = int("1" + lock[i])
            temp = int(unlock[i])
    else:
        continue
    
    if ((temp2 - temp) < (abs(int(lock[i]) - int(unlock[i])))):
        if temp2 == 10:
            moves += (temp2 - temp) + 1
        else:
            moves += temp2 - temp
    elif ((temp2 - temp) >= (abs(int(lock[i]) - int(unlock[i])))):
        moves += abs(int(lock[i]) - int(unlock[i]))
        
print(moves)