Generates all the possible permutations of the items in collection, in lexicographical order. Even if some items are equal, the same permutation will not be generated more than once. For example, if the collections contains the three items A, A, and B, then this method will generate only the three permutations, AAB, ABA, BAA.

Generates all the possible permutations of the items in collection, in lexicographical order. A supplied IComparer<T> instance is used to compare the items. Even if some items are equal, the same permutation will not be generated more than once. For example, if the collections contains the three items A, A, and B, then this method will generate only the three permutations, AAB, ABA, BAA.

Generates all the possible permutations of the items in collection, in lexicographical order. A supplied Comparison<T> delegate is used to compare the items. Even if some items are equal, the same permutation will not be generated more than once. For example, if the collections contains the three items A, A, and B, then this method will generate only the three permutations, AAB, ABA, BAA.