public static void traverse(LinkedListNode head) {
if (head == null) return;
StringBuffer buffer = new StringBuffer();
while (head != null) {
buffer.append(head.getData() + "->");
// remember to move
head = head.getNext();
}
buffer.append("null");
System.out.println(buffer.toString());
}
/** Get data stored in tail node of list. */
public T getLast() {
// set a LinkedListNode to get the current Node
LinkedListNode<T> currentNode = head;
// As long as there is a node with data after the current Node
while (currentNode.getNext() != null) {
// shift to set the next node as the current Node
currentNode = currentNode.getNext();
}
// When there is no node after the current Node return the data in the
// current Node
return currentNode.getData();
}
public static LinkedListNode NumbersAddition(LinkedListNode n1, LinkedListNode n2) {
// number 1 and number 2 may not have the same number of digits.
if (n1 == null || n2 == null) return null;
LinkedListNode sumHead = null;
LinkedListNode sumTail = null;
int advance = 0;
while (n1 != null || n2 != null) {
int digitSum = 0;
if (n1 != null && n2 != null) digitSum = n1.getData() + n2.getData() + advance;
else if (n1 == null) digitSum = n2.getData() + advance;
else digitSum = n1.getData() + advance;
if (digitSum >= 10) {
advance = 1;
digitSum = digitSum % 10;
} else {
advance = 0;
}
LinkedListNode dSum = new LinkedListNode();
dSum.setData(digitSum);
if (sumHead == null) sumHead = dSum;
if (sumTail == null) {
sumTail = dSum;
} else {
sumTail.setNext(dSum);
sumTail = dSum;
}
// move n1 and n2 under certain conditions!
if (n1 != null) n1 = n1.getNext();
if (n2 != null) n2 = n2.getNext();
}
if (advance == 1) {
LinkedListNode last = new LinkedListNode();
last.setData(advance);
sumTail.setNext(last);
sumTail = last;
}
return sumHead;
}
/** Return a String representation of the list. */
public String toString() {
// set a LinkedListNode to get the current Node
LinkedListNode<T> currentNode = head;
String s = "{";
// As long as there is a node with data after the current Node
while (currentNode != null) {
s = s + " " + currentNode.getData();
// shift to set the next node as the current Node
currentNode = currentNode.getNext();
}
// When there is no node after the current Node return the data in the
// current Node
s = s + "}";
System.out.println("The list is " + s);
return s;
}