# Problem O

WordSpin

Žofka invented a new word puzzle. She gives you two strings
$s_1$ and $s_2$ of the same length. You need to
modify $s_1$ into
$s_2$ as quickly as
possible. The trick is that you are allowed to modify the
strings only using the following types of moves: (1) shift
forward where you choose a substring of one of the strings and
shift each of its letters by 1 forward in the alphabet, or (2)
shift backward where you shift each letter in a substring
backward in the alphabet. The first move is not allowed if the
substring contains the letter `z` while the
second move is not allowed if the subtring contains `a`. What is the smallest number of moves you need to
modify $s_1$ into
$s_2$?

## Input

Each word puzzle is described on a single line that contains the strings $s_1$ and $s_2$ separated by space. The strings contain only lower case letters. You may also assume that the length of each string is at most $10\, 000\, 000$.

## Output

Output one line with the smallest number of moves needed to modify $s_1$ into $s_2$.

## Note

The first sample input can be modified in the following way.
First shift `lo` forward, getting `helmp`. Then shift `h` forward 12
times, getting `telmp`. Then shift `l` 11 times backward to get `teamp`
and then shift `p` forward three times to get
`teams`. Total number of moves is
$1+12+11+3=27$.

The second sample input can be modified as follows. First
shift the entire string forward, getting `bbdddbbbb`. Then shift `ddd`
backward twice to get `bbbbbbbbb`. This
requires 1+2=3 moves.

Sample Input 1 | Sample Output 1 |
---|---|

hello teams |
27 |

Sample Input 2 | Sample Output 2 |
---|---|

aacccaaaa bbbbbbbbb |
3 |