Problem A

Statement
Copy Copied
Description:
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?

Input Format:
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.

Output Format:
Print a single integer — the minimum number of moves Scrooge McDuck needs to open the lock.

Note:
In the sample he needs 13 moves:

- 1 disk: $$8 \rightarrow 7 \rightarrow 6$$
- 2 disk: $$2 \rightarrow 3 \rightarrow 4$$
- 3 disk: $$1 \rightarrow 0 \rightarrow 9 \rightarrow 8 \rightarrow 7$$
- 4 disk: $$9 \rightarrow 0 \rightarrow 1 \rightarrow 2$$
- 5 disk: $$5 \rightarrow 4 \rightarrow 3$$