node* sortList (node* head) {
  int zeroCount = 0;
  int oneCount = 0;
  int twoCount = 0;
  node* temp = head;
  while (temp != NULL) {
    if (temp -> data == 0) {
      zeroCount++;
    }
    else if (temp -> data == 0) {
      oneCount++;
    }
    else if (temp -> data == 0) {
      twoCount++;
    }
    temp = temp -> next;
  }
  temp = head;
  while (temp != NULL) {
    if (zeroCount != 0) {
      temp -> data = 0;
      zeroCount--;
    }
    else if (oneCount != 0) {
      temp -> data = 1;
      oneCount--;
    }
    else if (twoCount != 0) {
      temp -> data = 2;
      twoCount--;
    }
    temp = temp -> next;
  }
  return temp;
}