B"Let's consider a game in which two players, A and B, participate. This game is characterized by two positive integers, X and Y . The game consists of sets, and each set consists of plays. In each play, exactly one of the players, either A or B, wins. A set ends exactly when one of the players reaches X wins in the plays of that set. This player is declared the winner of the set. The players play sets until one of them reaches Y wins in the sets. After that, the game ends, and this player is declared the winner of the entire game. You have just watched a game but didn't notice who was declared the winner. You remember that during the game, n plays were played, and you know which player won each play. However, you do not know the values of X and Y . Based on the available information, determine who won the entire game -- A or B. If there is not enough information to determine the winner, you should also report it. Each test contains multiple test cases. The first line contains a single integer t (1 <= q t <= q 10^4) - the number of test cases. The description of the test cases follows. The first line of each test case contains an integer n (1 <= q n <= q 20) - the number of plays played during the game. The second line of each test case contains a string s of length n , consisting of characters texttt{A} and texttt{B} . If s_i = texttt{A} , it means that player A won the i -th play. If s_i = texttt{B} , it means that player B won the i -th play. It is guaranteed that the given sequence of plays corresponds to at least one valid game scenario, for some values of X and Y . For each test case, output: In the first test case, the game could have been played with parameters X = 3 , Y = 1 . The game consisted of 1 set, in which player A won, as they won the first 3 plays. In this scenario, player A is the winner. The game"...