在n×n格的棋盘上放置彼此不受攻击的n个皇后，按照国际象棋的规则，皇后可以攻击与之处在同一行或同一列或同一斜线上的棋子，求解可以放置的方法种数。-Placed on the n × n chessboard grid　attack each other n-queens, in accordance with the rules of chess, the queen can attack in the same row or column, or diagonal pieces of the same on the way to solving the species can be placed number.