回溯.rar是一种系统地搜索问题的解的方法。回溯算法的基本思想是：从一条路往前走，能进则进，不能进则退回来，换一条路再试。-Back. Rar is a systematic search of the solution method. The basic idea of backtracking algorithm is: from one way forward, can be entered into, can not enter the return to, try another ro

recall.c：回溯法求有向图是否存在回路，将结果输出到文件中。dfs.c：深度优先搜索解决N皇后问题，结果输出到文件。Client.java：一个java编写的即时通讯小程序。-recall. depth-first search. Instant message.

This program is to give you practice in the use of UNIX functions fork() and pipe() and to implement message communication between processes. In this program you will implement a simple UNIX shell in C. The shell reads a command line from the input,