Description

Little L abstracts the plot of movie A as a string $s_1$ of length $n$.

Little L abstracts the plot of movie B as a string $s_2$ of length $m$.

If Little L can insert any string (which can be empty) either before $s_1$ or after any character in $s_1$ to obtain a new string ${s_1}'$ such that ${s_1}' = s_2$, then we say movie B is "Yolo".

Little L has a total of $T$ queries. For each query, you need to determine whether movie B is "Yolo". If yes, output Yes; otherwise, output No.

Input Format

This problem contains multiple test cases.

The first line contains a positive integer $T$, the number of test cases.

For each test case:

• The first line contains two positive integers $n$ and $m$, separated by a space, representing the lengths of strings $s_1$ and $s_2$.
• The second line contains the string $s_1$.
• The third line contains the string $s_2$.

Output Format

Output $T$ lines, each containing either Yes or No, indicating whether movie B is "Yolo".

9
3 4
aab
aabb
3 5
xyz
xabyz
3 5
xyz
axbyz
4 4
aabb
aabb
3 3
aab
abb
4 6
abgd
xyabgd
4 6
abgd
abgdgd
3 6
abb
aabbab
3 6
abb
aabbbb

Yes
Yes
No
Yes
No
Yes
Yes
No
Yes

Hint

Explanation of Sample 1:

For the first test case, you can insert the string b after the last character of $s_1$ to get ${s_1}' = \texttt{aabb}$.

For the second test case, you can insert the string ab after the first character of $s_1$ to get ${s_1}' = \texttt{xabyz}$.

For the third test case, it can be proven that no such operation exists to make ${s_1}' = s_2$.

For the fourth test case, you can insert an empty string after the third character of $s_1$ to get ${s_1}' = \texttt{aabb}$.

For the sixth test case, you can insert the string xy before $s_1$ to get ${s_1}' = \texttt{xyabgd}$.

Constraints

Special Property A: $n = m$.

Special Property B: $n = m - 1$.

For $100\%$ of the test cases:

• $1 \leq T \leq 10$,
• $1 \leq n \leq m \leq 10^5$,
• Strings $s_1$ and $s_2$ consist of lowercase letters only.

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