import java.util.ArrayList;
import java.util.List;
public class Combination {
char[] chars={'a','b','c','d'};
List<Character> list=new ArrayList<Character>();
public void getCombination(char[] chars,List<Character> list,int i)
{
if(i==chars.length)
{
for(int j=0;j<list.size();j++)
{
System.out.print(list.get(j)+" ");
}
System.out.println();
}
else
{
list.add(chars[i]);
getCombination(chars,list,i+1);
boolean re=list.remove((Object)chars[i]);
if(re)
{
getCombination(chars,list,i+1);
}
}
}
public static void main(String[] args) {
Combination com=new Combination();
com.getCombination(com.chars, com.list, 0);
}
}
运行结果: