leetcode(2) Add Two Numbers-优快云博客

本文链接：https://blog.youkuaiyun.com/specialshoot/article/details/50659315

本文将介绍如何利用Java实现链表相加的功能，包括处理进位和创建新链表的过程。通过实例演示，深入理解链表操作和算法应用。

摘要生成于 C知道，由 DeepSeek-R1 满血版支持，前往体验 >

题目链接:https://leetcode.com/problems/add-two-numbers/

You are given two linked lists representing two non-negative numbers. 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.

Input: (2 -> 4 -> 3) + (5 -> 6 -> 4)
Output: 7 -> 0 -> 8

Subscribe to see which companies asked this question

带进位的列表相加,2+5=7,4+6=10,进位1,第二个数为0,3+4+进位1第三个数为8.

这道题比较简单,对每个表的同位进行相加然后求/,放到新列表中即可

java代码:

package leetcode;

public class AddTwoNumbers {

	// https://leetcode.com/problems/add-two-numbers/
	// Definition for singly-linked list.
	public static class ListNode {
		int val;
		ListNode next;

		ListNode(int x) {
			val = x;
		}
	}

	public static ListNode addTwoNumbers(ListNode l1, ListNode l2) {
		int carry = 0;

		ListNode newHead = new ListNode(0);
		ListNode p1 = l1, p2 = l2, p3 = newHead;

		while (p1 != null || p2 != null) {
			if (p1 != null) {
				carry += p1.val;
				p1 = p1.next;
			}

			if (p2 != null) {
				carry += p2.val;
				p2 = p2.next;
			}

			p3.next = new ListNode(carry % 10);
			p3 = p3.next;
			carry /= 10;
		}

		if (carry == 1)
			p3.next = new ListNode(1);

		return newHead.next;
	}

	public static void main(String agrs[]) {
		ListNode l1 = new ListNode(0), l2 = new ListNode(0);
		l1.val = 2;
		l1.next = new ListNode(4);
		l1.next.next = new ListNode(3);

		l2.val = 5;
		l2.next = new ListNode(6);
		l2.next.next = new ListNode(4);
		ListNode result = addTwoNumbers(l1, l2);
		while (result.next != null) {
			System.out.println(result.val);
			result = result.next;
		}
		System.out.println(result.val + "");
	}

}