import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
public class Test {
static String[] t1 = {"a","b","c"};
static String[] t2 = {"x","y","z"};
static List list = new ArrayList();
static Map map = new HashMap();
/**
* @param args
*/
public static void main(String[] args) {
for(int i=0;i<3;i++){
for(int j=0;j<3;j++){
if(t1[i].equals("a") && t2[j].equals("x")){
continue;
}
if(t1[i].equals("c") && t2[j].equals("x")){
continue;
}
if(t1[i].equals("c") && t2[j].equals("z")){
continue;
}
if(map.containsKey(t1[i])){
map.put(t1[i], map.get(t1[i]) + 1);
}else{
map.put(t1[i],1);
}
if(map.containsKey(t2[j])){
map.put(t2[j], map.get(t2[j]) + 1);
}else{
map.put(t2[j],1);
}
list.add(String.valueOf(t1[i])+":"+String.valueOf(t2[j]));
}
}
for(Map.Entry entry:map.entrySet()){
if(entry.getValue() == 1){
removeFromList(entry.getKey());
}
}
for(String s : list){
System.out.println(s);
}
}
public static void removeFromList(String c){
String sub = "";
for(int i=0,l=list.size();i if(list.get(i).contains(c+":")){
sub = list.get(i);
c = sub.split(":")[1];
break;
}else if(list.get(i).contains(":"+c)){
sub = list.get(i);
c = sub.split(":")[0];
break;
}
}
Iterator iter = list.iterator();
while(iter.hasNext()){
String s = iter.next();
if(!s.equals(sub) && s.contains(c+":")){
iter.remove();
}
if(!s.equals(sub) && s.contains(":"+c)){
iter.remove();
}
}
}
}