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.
import sys

#input = [str(a.strip()) for a in sys.stdin.readlines()]

#input = ["12","102021090898","010212908089"]

#print(input)

discs = int(input[0])
initial = input[1]
key = input[2]


totalMoves = 0
for i in range(0, discs):
    digitInitial = int(initial[i])
    digitKey = int(key[i])

    if(digitKey == digitInitial):
        break

    if(abs(digitInitial-digitKey) <= 5):
        totalMoves += abs(digitInitial-digitKey)
    else:
        totalMoves += 10 - abs(digitInitial-digitKey)

print(totalMoves)