求一段有关组合的C#代码

在文件夹里有最多324个文本文件(txt1.txt-txt324.txt),每个文件有30万行数据，每个文本里面的数据格式如下：
A1A5A11A33A64A79:01,02,03,04,05,06
A2A10A17A20A62A73:01,02,03,04,05,10
A4A14A26A34A61A67:01,02,03,04,05,11
A3A10A26A47A48A62:01,02,03,04,05,12
A3A20A32A34A41A48:01,02,03,04,05,15
A2A3A4A14A34A76:01,02,03,04,05,19
A2A3A14A26A34A50:01,02,03,04,05,20
A3A26A41A47A48A77:01,02,03,04,05,21
A3A4A14A26A34A61:01,02,03,04,05,23
A2A3A4A14A26A34:01,02,03,04,05,24
A2A10A62A63A68A73:01,02,03,04,05,25
A2A3A4A17A34A76:01,02,03,04,05,27
A2A4A14A22A76A80:01,02,03,04,05,30
A3A10A17A26A62A78:01,02,03,04,05,33
A3A8A29A32A36A38:01,02,03,04,06,08
A1A11A29A33A53A79:01,02,03,04,06,09
A2A8A10A17A62A73:01,02,03,04,06,10
A2A3A8A32A73A77:01,02,03,04,06,13

要求：
从324个文本文件(txt1.txt-txt324.txt)中每次抽取R个文件做交集(C(324,R)),每完成一次交集(只对冒号后面的数字交集)就将结果输出到一个单独的文本文件中(如：out1.txt，out2.txt，out2.txt。。。)。

顶一个 自力更生吧