public class Eserc1 {

    public static String fondi(String a,String b){

    if (!(a.length()==0) && !(b.length()==0)){


    boolean prima = (a.charAt(0)=='a' || a.charAt(0)=='e' || a.charAt(0)=='i' || a.charAt(0)=='o' || a.charAt(0)=='u');
    boolean seconda = (!(b.charAt(0)=='a') && !(b.charAt(0)=='e') && !(b.charAt(0)=='i') && !(b.charAt(0)=='o') && !(b.charAt(0)=='u'));

    if(prima && seconda)
    return a.charAt(0)+b.charAt(0)+ fondi(a.substring(1),b.substring(1));
     else if(prima)
     return fondi(a,b.substring(1));
       else if(seconda)
       	return fondi(a.substring(1),b);
       	else return fondi(a.substring(1),b.substring(1));


    }

     else if(!(a.length()==0))
     return a;


     else if(!(b.length()==0))
     return b;



     else return " ";

    }


}