回複:ZT:平麵上7個點(3星)

來源: 2009-07-03 06:52:26 [舊帖] [給我悄悄話] 本文已被閱讀:

A. 3 points form a triangle with each edge of 1.
B. 4 points form a square with each edge of 1.
place A and B at a plane separated far enough that any point in one group to any point of another group is large than 1.