【LeetCode】2. Add Two Numbers

最新推荐文章于 2024-01-03 15:29:28 发布

原创最新推荐文章于 2024-01-03 15:29:28 发布 · 101 阅读

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本文介绍了一种解决两数相加问题的链表实现方法，通过遍历两个链表并逐位相加，处理进位，最终返回相加结果的链表。文章详细展示了如何使用链表节点来存储数字，并在链表中进行加法运算。

题目：

You are given two non-empty linked lists representing two non-negative integers. The digits are stored in reverse order and each of their nodes contain a single digit. Add the two numbers and return it as a linked list.

You may assume the two numbers do not contain any leading zero, except the number 0 itself.

第一次写medium，看了一些youtube的视频，更好的理解了linkedlist会写的好快鸭。。。。

Code：

public ListNode addTwoNumbers(ListNode l1, ListNode l2) {
 
int carry = 0;
ListNode dummy = new ListNode(0);
ListNode l3 = dummy;
    
while(l1!=null && l2!=null){
  int digitalval = (l1.val+l2.val+carry)%10;
  carry = (l1.val+l2.val+carry)/10;
  ListNode newnode = new ListNode(digitalval);
  l3.next = newnode;
  l3 = newnode;
  l1=l1.next;
  l2=l2.next; 
}

while(l1 !=null){
    int digitalval = (l1.val+carry)%10;
    carry = (l1.val+carry)/10;
    ListNode newnode = new ListNode(digitalval);
    l3.next = newnode;
    l3 = newnode;
    l1 = l1.next;
}
    
while(l2 !=null){
    int digitalval = (l2.val+carry)%10;
    carry = (l2.val+carry)/10;
    ListNode newnode = new ListNode(digitalval);
    l3.next = newnode;
    l3 = newnode;
    l2 = l2.next;
}

if(carry!=0){
    ListNode newnode = new ListNode(carry);
    l3.next = newnode;
    l3 = newnode;
}
 return dummy.next;   
}