You are given two strings A and B of length N consisting of lowercase English letters. Your objective is to make both the strings equal.

You can apply one of the following 2 operations at each index i:
Convert char A_{i} to B_{i} by doing right cyclic shift of character A_{i}. This increases your score by amount equal to cyclic shifts done.
Convert char B_{i} to A_{i} by doing right cyclic shift of character B_{i}. This decreases your score by amount equal to cyclic shifts done.

Your starting score is zero.
If the operations are applied optimally, find the minimum [absolute] score possible after making both the strings equal.

Note: A single right cyclic shift converts one character to the next in alphabetical order, except for z which goes to a. That is, the sequence looks like

$a \to$ $b \to$ $c \to$ $\ldots \to$ $y \to$ $z \to$ $a \to$ $b \to$ $\ldots$

So, for example converting a to e requires 4 right cyclic shifts, and converting k to i requires 24.

------ Input Format ------

• The first line of input will contain a single integer T, denoting the number of test cases.
• Each test case consists of three lines of input.
• The first line of each test case contains one integer N — the length of strings A and B.
• The second line contains string A.
• The third line contains string B.

------ Output Format ------

For each test case, output on a new line the minimum absolute score possible after making both the strings equal.

------ Constraints ------

$1 ≤ T ≤ 100$
$1 ≤ N ≤ 10^{5}$
- Both strings $A$ and $B$ have same length $N$ and contain only lowercase English letters.
- The sum of $N$ over all test cases won't exceed $10^{5}$.

----- Sample Input 1 ------
4
3
abb
baz
3
zzc
aaa
4
fxbs
dkrc
5
eaufq
drtkn

----- Sample Output 1 ------
2
0
11
9

----- explanation 1 ------
Test case $1$: The minimum absolute score can be obtained as follows:
- Apply operation $1$ at position $1$, converting $a$ to $b$ for a cost of $+1$.
- Apply operation $2$ at position $2$, converting $a$ to $b$ for a cost of $-1$.
- Apply operation $2$ at position $3$, converting $z$ to $b$ for a cost of $-2$.

The score is then $1 -1 -2 = -2$, with absolute value $2$. This is the lowest possible absolute value attainable.

Test case $2$: Apply operations as follows:
- Operation $1$ at index $1$, $z\to a$ for a cost of $+1$
- Operation $1$ at index $2$, $z\to a$ for a cost of $+1$
- Operation $2$ at index $3$, $a\to c$ for a cost of $-2$

This gives us a final score of $1 + 1 - 2 = 0$, which has absolute value $0$. It is not possible to do better than this.

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