在m行n列棋盘的S点处有一中国象棋马，给出棋盘上的另一点T，设T在S的右边（如下图所示）。规定马走日字且只能向右走，要从S走到T，马至少要走多少步?-In the m line n chessboard out of the S point has one Chinese chess horse, given chessboard another point T, located the right side of T in S (as in the figure below). Ma date