著名的八皇后问题，是回溯算法的典型例题。该问题是19世纪著名的数学家高斯1850年提出：在8*8格的国际象棋上摆放8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。-The famous Eight Queens problem, backtracking algorithm is a typical example. The problem is the famous 19th century mathematician Gauss 1850: Under the 8* 8 grid placed on 8 chess queens, so that it can not attack each other, that any two of the Queen can not in the same row, same column or the same diagonal, asked how many kinds of pendulum method.