I am trying to find a way to get a list in R of all the possible unique permutations of A,A,A,A,B,B,B,B,B. I am trying to find a way to get a list in R of
阅读背景：
R A，A，A，A，B，B，B，B，B的唯一组合的问题编号
来源：互联网
分享到：
