difficult recursion problem in C

[dan.b]

Hi, everybody.
I really need your help with this question that giving me no sleep at nights. :(


no loops and no pointers, and No STATIC can be used.
Write a recursive function that fills the given character
array with all possible given-size subsets of characters in
given word, separated by commas

does anyone have an idea?

[D H]

No pointers? The function takes two pointers as arguments!

The order of the desired output strongly indicates you should be looking at a depth first recursion technique.

[dan.b]

it means no using *types, calling to r as an address in the array is fine.
what is first recursion technique can you add an exmple?

[mXSCNT]

The subsets of size m of the numbers 1,2,...n are:
1, added at the beginning of the subsets of size m-1 of the numbers 2,3,...,n
followed by the subsets of size m of 2,...,n
This doesn't consider the base cases--base cases are when m=0, or when the range of numbers considered is empty.

[D H]

That's a bit too much help, mXSCNT.

[mXSCNT]

Alright, I'll delete the second part.