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.

def rotar_derecha(num_ini, num_fin):
	numbers = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
	num_moves = 0

	while numbers[0] != num_ini:

		first_num = numbers[0]
		last_num = numbers[-1]
		for i in range(1, len(numbers)):
			first_num = numbers[0]
			numbers[ len(numbers)-i ] = numbers[ len(numbers)-(i+1) ]
		numbers[0] = last_num

	while numbers[0] != num_fin:

		first_num = numbers[0]
		last_num = numbers[-1]
		for i in range(1, len(numbers)):
			first_num = numbers[0]
			numbers[ len(numbers)-i ] = numbers[ len(numbers)-(i+1) ]
		numbers[0] = last_num
		num_moves = num_moves + 1

	return num_moves



def rotar_izquierda(num_ini, num_fin):
	numbers = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
	num_moves = 0

	while numbers[0] != num_ini:

		first_num = numbers[0]
		for i in range(0, len(numbers)-1):
			first_num = numbers[0]
			numbers[i] = numbers[i+1]
		numbers[9] = first_num

	while numbers[0] != num_fin:
		
		first_num = numbers[0]
		for i in range(0, len(numbers)-1):
			first_num = numbers[0]
			numbers[i] = numbers[i+1]
		numbers[9] = first_num
		num_moves = num_moves + 1

	return num_moves


def init():
	disks = int(input())
	original_pos = input()
	password = input()
	numbers = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
	total_moves = 0
	
	for i in range(0, disks):
		num1 = int(original_pos[i])
		num2 = int(password[i])
		moves1 = rotar_izquierda(num1, num2)
		moves2 = rotar_derecha(num1, num2)
		
		if moves1 < moves2:
			total_moves = total_moves + moves1
		else:
			total_moves = total_moves + moves2
	
	print(total_moves+1)


if __name__ == "__main__":
	init()
