I need help on a program in C. I would like you to ask the user what word they would like to enter in the system to find out how many combinations of letters there might be. Then output all of the combinations of letters in the word. You must use recursion to do this. Also dynamically allocate memory for the string that is entered. Also, the program must not print out duplicates. For example the word dull. Because there are two l's in the word, a simple program would switch the l's and dlul and dlul would seem like two different words to the program. Please avoid this and do not print out duplicates.

Example of Program:

(Printf) What word would you like to enter?

(User Enters): buy

(Printf): buy, byu, uby, uyb, yub, ybu

Thank You!

*** This is in C