题解 | #链表相加(二)#

import java.util.*;

/*
 * public class ListNode {
 *   int val;
 *   ListNode next = null;
 *   public ListNode(int val) {
 *     this.val = val;
 *   }
 * }
 */

public class Solution {
    /**
     * 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
     *
     * 
     * @param head1 ListNode类 
     * @param head2 ListNode类 
     * @return ListNode类
     */
    public ListNode addInList (ListNode head1, ListNode head2) {
        // write code here
        LinkedList<ListNode> stack1 = new LinkedList<>();
        LinkedList<ListNode> stack2 = new LinkedList<>();
        ListNode cur = head1;
        while(cur!=null){
            stack1.add(cur);
            cur = cur.next;
        }
        cur = head2;
        while(cur!=null){
            stack2.add(cur);
            cur = cur.next;
        }
        int plus = 0;
        ListNode head = new ListNode(0);
        while(!stack1.isEmpty()|| !stack2.isEmpty()){
            int i1 = 0;
            int i2 = 0;
            if(!stack1.isEmpty()){
                i1 = stack1.removeLast().val;
            }
            if(!stack2.isEmpty()){
                i2 = stack2.removeLast().val;
            }
            int value = i1+i2+plus;
            if(value>9){
                plus = value/10;
                value = value%10;
            }else{
                plus = 0;
            }
            ListNode node = new ListNode(value);
            System.out.println(value);
            node.next = head.next;
            head.next = node;
        }
        if(plus>0){
            head.val = plus;
            return head;
        }else{
            return head.next;
        }


    }
}