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 math
def gcd (a, b):
    if a % b == 0:
        return b
    else:
        return gcd(b, a%b)    

def prime_bool(k):
    if k==2 or k==3: return True
    if k%2==0 or k<2: return False
    for i in range(3, int(k**0.5)+1, 2):
        if k%i==0:
            return False
    return True

def prime(k):
    for i in range(2, int(k**0.5)+1, 1):
        if k%i==0:
            return i
    return k

def isstep2(num):
    if num == 1:
        return True
    if num & 1:
        return False
    return isstep2(num >> 1)




n = int(input())
a = input()
b = input()
ans = 0
for i in range(n) :
    x = int(a[i])
    y = int(b[i])
    ans += min(abs(x - y), abs(10 - abs(y - x)))
print(ans)