cc150_2_5.java

/*
Created by bitcpf
*/



public class Addup {
	
	public static Node Addlist(Node head1, Node head2, int up_dig){
		int digit_add;
		
		if(head1 == null && up_dig ==0){
			return head2;
		}
		if(head2 == null && up_dig == 0){
			return head1;
		}
		
		if(head2 == null && head1 == null){
			if(up_dig != 0){
				digit_add = 0;
			}
			else{
				return null;
			}
		}
		else{
			if(head1 == null){
				digit_add = head2.getval();
			}
			else if(head2 == null){
				digit_add = head1.getval();
			}
			else{
			digit_add = (head1.getval() + head2.getval());
			}
		}



		
		
		Node rs_head = new Node((digit_add+up_dig)%10);
			
		int flag = (digit_add+up_dig)/10;

		
		if(head1 != null || head2 != null || flag!= 0){
			if(head1 == null && head2 == null){
				rs_head.next = Addlist(null,null,flag);
			}
			else if(head1 == null){
				rs_head.next = Addlist(null,head2.next,flag);
			}
			else if(head2 == null){
				rs_head.next = Addlist(head1.next,null,flag);
			}
			else{
				rs_head.next = Addlist(head1.next,head2.next,flag);
			}
		}
		
		
		return rs_head;
	}
	
	
	
	public static void printlist(Node head){
		while(head.next != null){
			System.out.print(head.item);
			head = head.next;
		}
		System.out.println(head.item);
	}
	
	public static void main(String[] args){
		Node f_1 = new Node(7);
		Node f_2 = new Node(1);
		Node f_3 = new Node(6);
		Node f_4 = new Node(9);
		
		f_1.next = f_2;
		f_2.next = f_3;
		f_3.next = f_4;

		Node s_1 = new Node(5);
		Node s_2 = new Node(9);
		Node s_3 = new Node(3);

		s_1.next = s_2;
		s_2.next = s_3;

		
		printlist(f_1);
		printlist(s_1);
		printlist(Addlist(f_1,s_1,0));
	}

}

Node.java

public class Node<Item> {

	Item item = null;
	Node next = null;
	
	public Node(Item input){
		this.item = input;
		this.next = null;
	}
	
	public int getval(){
		return (Integer) (this.item);
	}
	
}