I need a function that can give me all possible combinations of a array back.
Example:
$source = array('a', 'b', 'c');
$target = thisiswhatisearch($source);
Now the $target should look like:
array('a','b','c','ab','ac','cb','abc')
I dont need the aa, bb, cc.
I also dont need the the ba, ca, acb.. because the order isn't important to me.
Thanks for any help.
Tried to be language agnostic but i guess its C like:
function combinations(array arr)
{
combos = array();
for (int i=1; i<2**arr.size(); i++)
{
int x = i;
int c = 0;
str = "";
while(x>0)
{
int rem = x % 2;
if(rem == 1)
str += arr[c];
x = x / 2;
c++;
}
combos.add(str);
}
return combos;
}
The Wikipedia entry for Combination has a link to C code that does this.
That's an out of the mind solution. It is probably not the fastest and cleanest one, but it kind of works. It's in Java, because I had it open:
public class Combination {
public static void main(String[] args) {
String[] source = {"a","b","c"};
List<String> result = combineMe(new ArrayList<String>(Arrays.asList(source)));
for (String string : result) {
System.out.println(string);
}
}
public static List<String> combineMe(List<String> source) {
List<String> result = new ArrayList<String>();
if (source.size()==0) {
result.add("");
return result;
}else{
String tmp = source.remove(0);
source = combineMe(source);
for (String string : source) {
result.add(("" + string).trim());
result.add(tmp + string);
}
}
return result;
}
}
The first entry in the resulting list is a fake one, and needs to be removed at the end
