A Text Editor Imlementation。

对输入缓冲区中的文件内容进行编辑，包括：显示当前文件内容、到第一行、到最后一行、到前一行、到下一行、到指定的某一行、插入一行、删除一行、替换当前行、替换某个子串、查找指定的某个子串、统计文件行数及字符数、重新读入文件、保存当前文件、退出系统等操作-A Text Editor Imlementation 。edit the contents of the file in the input buffer, including: displays the current contents of the file to the first line to the last line to the front line to the next line, and a line to the specified insert a row, delete a row replace the current line, replace a substring, find a substring specified statistical document the number of rows and number of characters, re-read the file, save the current file and exit the system operation