Problem2-4.java

public void partitionList(Node head, int value) {
  Node small = null;
  Node smallItr = null;
  Node great = null;
  Node greatItr;
  while (head != null) {
    if (head.data < value) {
      if (smallItr == null) {
        small = smallItr = head;
      }
      else {
        // Add in between so we don't lose head
        smallItr.next = head;
        smallItr = smallItr.next;
      }
    }
    else {
      // greater than or equal
      if (greatItr == null) {
        great = greatItr = head;
      }
      else {
        greatItr.next = head;
        greatItr = greatItr.next;
      }
    }
    
    head = head.next;
  }
}