給定兩個有序單鏈表，合併成一個新的有序連結串列，分別用遞迴和非遞迴的方式實現如下：

package algorithm;

public class MergeSortLinkList {

	public static void main(String[] args) {
		Node[] nodes = createData();
		// Node node = mergeByRecursion(nodes[0], nodes[1]);
		Node node = merge(nodes[0], nodes[1]);
		print(node);
	}

	public static Node[] createData() {
		Node node1 = new Node(0, null);
		Node head1 = node1;
		Node node2 = new Node(0, null);
		Node head2 = node2;
		for (int i = 1; i <= 10; i++) {
			Node tmp1 = new Node(i, null);
			node1.next = tmp1;
			node1 = tmp1;
		}
		for (int i = 1; i <= 1000; i++) {
			Node tmp2 = new Node(i, null);
			node2.next = tmp2;
			node2 = tmp2;
		}
		Node[] nodes = new Node[2];
		nodes[0] = head1;
		nodes[1] = head2;
		return nodes;
	}

	public static Node mergeByRecursion(Node node1, Node node2) {
		if (node1 == null) {
			return node2;
		} else if (node2 == null) {
			return node1;
		}
		if (node1.value < node2.value) {
			node1.next = merge(node1.next, node2);
			return node1;
		} else {
			node2.next = merge(node2.next, node1);
			return node2;
		}
	}

	public static Node merge(Node node1, Node node2) {
		if (node1 == null) {
			return node2;
		} else if (node2 == null) {
			return node1;
		}
		//先得到頭部指標
		Node node = null;
		if (node1.value < node2.value) {
			node = node1;
			node1 = node1.next;
		} else {
			node = node2;
			node2 = node2.next;
		}
		//儲存頭部指標
		Node head = node;
		//迴圈移動節點
		while (node1 != null && node2 != null) {
			if (node1.value < node2.value) {
				node.next = node1;
				node = node1;
				node1 = node1.next;
			} else {
				node.next = node2;
				node = node2;
				node2 = node2.next;
			}
		}
		//當兩個連結串列長度不一致時的處理
		if (node1 == null) {
			node.next = node2;
		} else {
			node.next = node1;
		}
		return head;
	}

	public static void print(Node node) {
		while (node != null) {
			System.out.println(node.value);
			node = node.next;
		}
	}

}

class Node {
	public int value;
	public Node next;

	public Node(int value, Node next) {
		this.value = value;
		this.next = next;
	}
}