Hermione has a knows a magical spell to teleport words.
She can teleport words in two ways, each teleport takes a minute to work a and b. Help her to convert her move a to b
In a one minute, she can teleport any letter by spell a by one, that is, in a minute, she can convert letter A to B, B to C, C to D and so on. She can also teleport Z to A.
She comes to know that she can take help from Ron Weasley and can teleport any letter using spell b by 13 that is she can teleport any single letter by 13 like A to N, B into letter O, M into letter Z, O to B and so on.
Harry Potter challenges her to teleport by taking minimum time.
Help Hermione to accept the challenge and teleport faster....!!!
Constraints:
- 1≤|a|=|b|≤105
- a and b consists of uppercase English letters only
Input format:
- First line contains an integer n, the length of strings a and b
- Second line contains string a of length n
- Third line contains string b of length n
Output format:
- Output single line containing the minimum time required
Hermione can convert teleport with help of Ron from a to b in 7 minutes as follows:
1. A−>N (1st letter)
2. N−>O (1st letter)
3. O−>P (1st letter)
4. C−>D (3rd letter)
5. T−>G (4th letter)
6. G−>H (4th letter)
7. H−>I (4th letter)
