B'Qingshan has a string s , while Daniel has a string t . Both strings only contain texttt{0} and texttt{1} . A string a of length k is good if and only if For example, texttt{1} , texttt{101} , texttt{0101} are good, while texttt{11} , texttt{1001} , texttt{001100} are not good. Qingshan wants to make s good. To do this, she can do the following operation any number of times (possibly, zero): Please tell Qingshan if it is possible to make s good. The input consists of multiple test cases. The first line contains a single integer T ( 1 <= T <= 2000 ) -- the number of test cases. The description of the test cases follows. The first line of each test case contains two integers n and m ( 1 <= n,m <= 50 ) -- the length of the strings s and t , respectively. The second line of each test case contains a string s of length n . The third line of each test case contains a string t of length m . It is guaranteed that s and t only contain texttt{0} and texttt{1} . For each test case, print "YES" (without quotes), if it is possible to make s good, and "NO" (without quotes) otherwise. You can print letters in any case (upper or lower). In the first test case, s is good initially, so you can get a good s by doing zero operations. In the second test case, you can do the following two operations (the inserted string t is underlined): and get s = texttt{101010101} , which is good. In the third test case, there is no way to make s good after any number of operations. '...