对读入的某个文本文件input.txt中，拆出英文单词，输出一个按字典顺序排列的单词表，结果输出在文本文件output.txt中，每个单词一行，并在单词后输出该单词出现的个数，两个字段之间用逗号分隔。约定单词仅由英文字母组成，单词间由非英文字母分隔，相同单词只输出一个，大小写不区分。-Of reading a text file input.txt, the demolition of the English word, the output of a lexicographical order of word list, the resulting output file output.txt in the text, each word line, and after the output of the word in the word the number appears, between the two fields separated by commas. Agreed by the English letters only words, words separated by non-English letters, the same word in the output only one case does not distinguish.