AS3函数产生数组的组合，没有重复

Question

这听起来像一个重复的问题，因为有几个类似的问题，但他们没有具体问这个（或者我只是没有找到它！:)）我有一个数组，这个有两个不同的元素，“a”和“b”，以及四个总元素的长度：

    var list:Array = ["a","a","b","b"];

我正在寻找所有组合，使用所有元素，没有重复。这应该产生：

    aabb
    abab
    abba
    bbaa
    baba
    baab

为此寻找解决方案给了我类似的结果：

a，b，ab，ba，aab，abb，aba等或
a a b b，a b b，a b b等

请注意，最终使用此函数的应用程序将具有两个不同的元素：“a”和“b”，以及总共50个元素的长度：

    var list:Array = ["a","a","a","a","a","a","a","a","a","a",
                      "a","a","a","a","a","a","a","a","a","a",
                      "a","a","a","a","a",
                      "b","b","b","b","b","b","b","b","b","b",
                      "b","b","b","b","b","b","b","b","b","b",
                      "b","b","b","b","b"]

......所以像我和aabb一样使用蛮力解决方案是不可行的。

任何帮助，特别是使用AS3代码，将不胜感激，即使它只是指向我正确的谷歌搜索:)