java實現合併兩個有序單鏈表

public class MergeLink {

	public static void main(String[] args) {
		Scanner scanner = new Scanner(System.in);
		String str1 = scanner.nextLine();
		String str2 = scanner.nextLine();
		NodeList node1 = createNodeList(str1);
		NodeList node2 = createNodeList(str2);
		NodeList newNode = null;
		if(node1 !=null && node2 !=null){
			newNode = mergeLink(node1, node2);
		}
		System.out.println(newNode);
	}
	
	/**
	 * 創建單鏈表
	 * @param str
	 * @return
	 */
	public static NodeList createNodeList(String str){
		
		if(str ==null || str.length() <=0){
			return null;
		}
		
		char[] s = str.toCharArray();
		NodeList[] nodeLists = new NodeList[s.length];
		//初始化鏈表
		for(int i=0;i<s.length;i++){
			nodeLists[i] = new NodeList(s[i]);
		}
		
		//將鏈表連接起來
		for(int i=0;i<s.length;i++){
			if(i == s.length-1){
				nodeLists[i].next = null;
			}else {
				nodeLists[i].next = nodeLists[i+1];
			}
		}
		return nodeLists[0];
	}
	
	/**
	 * 將兩個有序的單鏈表合併
	 * @param node1
	 * @param node2
	 * @return
	 */
	public static NodeList mergeLink(NodeList node1,NodeList node2){
		if(node1 ==null){
			return node2;
		}
		if(node2 ==null){
			return node1;
		}
		
		NodeList newNodeList = null;
		if(node1.var <=node2.var){
			newNodeList = node1;
			newNodeList.next = mergeLink(node1.next,node2);
		}else {
			newNodeList = node2;
			newNodeList.next = mergeLink(node1,node2.next);
		}
		
		return newNodeList;
	}

}