送交者: gyro 于 2006-3-30, 11:38:23:

回答: U is combination operations which includes union, cross product 由 steven 于 2006-3-30, 11:15:16:

or a series of 原贴，跟贴 with certain mysterious theme?

• of course, it is concatenation if it appends to the original, - steven (80 bytes) 2006-3-30, 12:03:07

加跟贴