public String comboString(String a, String b) {
  if (a.length() > b.length()) {
    return b + a + b;
  }
  else {
    return a + b + a;
  }
}

public String comboString(String a, String b) {
  String shorter = a;
  String longer = b;
  if (a.length() > b.length()) {
    shorter = b;
    longer = a;
  }
  return shorter + longer + shorter;
}