题解 | #牛群的能量值#

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 l1 ListNode类
     * @param l2 ListNode类
     * @return ListNode类
     */
    public ListNode addEnergyValues (ListNode l1, ListNode l2) {
        // write code here
        ListNode head = new ListNode(-1);
        ListNode cur = head;
        int p = 0;
        while (l1 != null || l2 != null) {
            int x = l1 != null ? l1.val : 0;
            int y = l2 != null ? l2.val : 0;
            int num = (x + y + p) % 10;
            p = (x + y + p) / 10;
            cur.next = new ListNode(num);
            cur = cur.next;
            if (l1 != null)  l1 = l1.next;
            if (l2 != null)  l2 = l2.next;
        }
        cur.next = p == 0 ? null : new ListNode(1);
        return head.next;
    }
}