这是一个用c++实现的n后问题，利用回溯法，并以深度优先搜索的方法，进行求解，程序中由用户输入n值确定是几后问题，打出所有的解。-This is a used c++ Achieved after n problem, the use of backtracking, and depth-first search method to solve process n value is entered by the user to determine several issues, making a