链表是数据结构中的重要组成部分,通过对链表的学习可以提高对指针的理解。
1. 链表相加 (Add Two Numbers)

/**
* Definition for singly-linked list.
* struct ListNode {
* int val;
* ListNode *next;
* ListNode() : val(0), next(nullptr) {}
* ListNode(int x) : val(x), next(nullptr) {}
* ListNode(int x, ListNode *next) : val(x), next(next) {}
* };
*/
class Solution {
public:
ListNode* addTwoNumbers(ListNode* l1, ListNode* l2) {
ListNode* cur1 = l1, *cur2 = l2;
ListNode* newhead = new ListNode(0); // 虚拟头节点
ListNode* prev = newhead;
int t = 0;
while(cur1 || cur2 || t){
if(cur1){
t += cur1->val;
cur1 = cur1->next;
}
if(cur2){
t += cur2->val;
cur2 = cur2->next;
}
prev->next = new ListNode(t % 10);
prev = prev->next;
t /= 10;
}
prev = newhead->next;
delete newhead;
return prev;
}
};




