与用户进行“聊天”。提取了一行字，只包括字母和连字符的最后一个字。如果单词太长存储在目标字符串变量中，只有指定数目的字符被复制。-Program to "chat" with the user. Extract the last word from a line of words, only including alphabetic letters and hyphens. If the word is too long to store in the target string variabl