recursion resulting in extra unwanted data
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Published on 2010-06-07T17:36:01Z
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2010/06/07
17:42 UTC
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I'm writing a module to handle dice rolling. Given x die of y sides, I'm trying to come up with a list of all potential roll combinations.
This code assumes 3 die, each with 3 sides labeled 1, 2, and 3. (I realize I'm using "magic numbers" but this is just an attempt to simplify and get the base code working.)
int[] set = { 1, 1, 1 };
list = diceroll.recurse(0,0, list, set);
...
public ArrayList<Integer> recurse(int index, int i, ArrayList<Integer> list, int[] set){
if(index < 3){
// System.out.print("\n(looping on "+index+")\n");
for(int k=1;k<=3;k++){
// System.out.print("setting i"+index+" to "+k+" ");
set[index] = k;
dump(set);
recurse(index+1, i, list, set);
}
}
return list;
}
(dump() is a simple method to just display the contents of list[]. The variable i is not used at the moment.)
What I'm attempting to do is increment a list[index] by one, stepping through the entire length of the list and incrementing as I go.
This is my "best attempt" code. Here is the output:
Bold output is what I'm looking for. I can't figure out how to get rid of the rest. (This is assuming three dice, each with 3 sides. Using recursion so I can scale it up to any x dice with y sides.)
[1][1][1] [1][1][1]
[1][1][1] [1][1][2] [1][1][3] [1][2][3]
[1][2][1] [1][2][2] [1][2][3] [1][3][3]
[1][3][1] [1][3][2] [1][3][3] [2][3][3] [2][1][3]
[2][1][1] [2][1][2] [2][1][3] [2][2][3]
[2][2][1] [2][2][2] [2][2][3] [2][3][3]
[2][3][1] [2][3][2] [2][3][3] [3][3][3] [3][1][3]
[3][1][1] [3][1][2] [3][1][3] [3][2][3]
[3][2][1] [3][2][2] [3][2][3] [3][3][3]
[3][3][1] [3][3][2] [3][3][3]
I apologize for the formatting, best I could come up with.
Any help would be greatly appreciated. (This method was actually stemmed to use the data for something quite trivial, but has turned into a personal challenge. :)
edit: If there is another approach to solving this problem I'd be all ears, but I'd also like to solve my current problem and successfully use recursion for something useful.
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