B. Not Quite Latin Squaretime limit per test1 secondmemory limit per test256 megabytesinputstandard inputoutputstandard outputA Latin square is a 3 \times 3 grid made up of the letters \texttt{A}, \texttt{B}, and \texttt{C} such that:   in each row, the letters \texttt{A}, \texttt{B}, and \texttt{C} each appear once, and  in each column, the letters \texttt{A}, \texttt{B}, and \texttt{C} each appear once.  For example, one possible Latin square is shown below. \begin{bmatrix} \texttt{A} & \texttt{B} & \texttt{C} \\ \texttt{C} & \texttt{A} & \texttt{B} \\ \texttt{B} & \texttt{C} & \texttt{A} \\ \end{bmatrix}You are given a Latin square, but one of the letters was replaced with a question mark \texttt{?}. Find the letter that was replaced.InputThe first line of the input contains a single integer t (1 \leq t \leq 108) — the number of testcases.Each test case contains three lines, each consisting of three characters, representing the Latin square. Each character is one of \texttt{A}, \texttt{B}, \texttt{C}, or \texttt{?}.Each test case is a Latin square with exactly one of the letters replaced with a question mark \texttt{?}.OutputFor each test case, output the letter that was replaced.ExampleInput
3ABCC?BBCABCACA?ABC?ABBCAABCOutput
A
B
C
NoteThe correct Latin squares for the three test cases are shown below:\begin{bmatrix} \texttt{A} & \texttt{B} & \texttt{C} \\ \texttt{C} & \color{red}{\texttt{A}} & \texttt{B} \\ \texttt{B} & \texttt{C} & \texttt{A} \\ \end{bmatrix} \quad \begin{bmatrix} \texttt{B} & \texttt{C} & \texttt{A} \\ \texttt{C} & \texttt{A} & \color{red}{\texttt{B}} \\ \texttt{A} & \texttt{B} & \texttt{C} \\ \end{bmatrix} \quad \begin{bmatrix} \color{red}{\texttt{C}} & \texttt{A} & \texttt{B} \\ \texttt{B} & \texttt{C} & \texttt{A} \\ \texttt{A} & \texttt{B} & \texttt{C} \\ \end{bmatrix}
3ABCC?BBCABCACA?ABC?ABBCAABC
A B C 
['bitmasks', 'brute force', 'implementation', '*800']