八皇后问题，是一个古老而著名的问题，是回溯算法的典型案例。该问题是国际西洋棋棋手马克斯·贝瑟尔于1848年提出：在8×8格的国际象棋上摆放八个皇后，使其不能互相攻击，即任意两个皇后都不能处于同一行、同一列或同一斜线上，问有多少种摆法。-Eight queens problem is an old and well-known problem is backtracking algorithms typical case. The problem is that international chess players Spey Mark Searle in 1848 stated: put eight queens on a chess grid 88, it can not attack each other, that is, any two queens are not in the same row, the same column or the same slash and asked how many pendulum method.