How to compute Permutation of 4P3?

Let's say i create a String array that store 4 Alphabets {"A","B","C","D"}
How can i get the result if i need permutation of 4P3 and 4P2?

I had refer to many examples from the internet, but those examples cannot compute n selection from m elements. They only able to computer permutation of m elements without selection e.g. 4P4.

I need help in how to create an algorithm that can perform permutation of n selection from m elements.

Any help will be appreciated.

Thanks
Ash

re: How to compute Permutation of 4P3?

The sequence nCm can be easily generated; for every element in nCm generate all its permutations mPm (which is also easy).

kind regards,

Jos

re: How to compute Permutation of 4P3?

I think Random class can help you alot in this regard.......Post more what you intend to do ......