C# · 12月 20, 2021

LeetCode2两数相加-C语言

给出两个 非空 的链表用来表示两个非负的整数。其中,它们各自的位数是按照 逆序 的方式存储的,并且它们的每个节点只能存储 一位 数字。

如果,我们将这两个数相加起来,则会返回一个新的链表来表示它们的和。

您可以假设除了数字 0 之外,这两个数都不会以 0 开头。

示例:

输入:(2 -> 4 -> 3) + (5 -> 6 -> 4)

输出:7 -> 0 -> 8

原因:342 + 465 = 807

/**

* DeFinition for singly-linked list.

* struct ListNode {

* int val;

* struct ListNode *next;

* };

*/

struct ListNode* addTwoNumbers(struct ListNode* l1,struct ListNode* l2) {

struct ListNode *l3 = (struct ListNode *)malloc(sizeof(struct ListNode));

struct ListNode *p1 = l1,*p2 = l2,*p3 = l3;

p3 -> next = NULL;

p3 -> val = 0;

while(p1 != NULL && p2 != NULL){

struct ListNode *node = (struct ListNode *)malloc(sizeof(struct ListNode));

node -> val = 0;

node -> next = NULL;

p3 -> next = node;

p3 -> val += p1 -> val + p2 -> val;

if(p3 -> val >= 10){

p3 -> val -= 10;

node -> val = 1;

}

p1 = p1 -> next;

p2 = p2 -> next;

if(p1 == NULL && p2 == NULL && p3 -> next -> val == 0)

{p3 -> next = NULL;}

p3 = p3 -> next;

}

while(p1 != NULL){

struct ListNode *node = (struct ListNode *)malloc(sizeof(struct ListNode));

node -> val = 0;

node -> next = NULL;

p3 -> next = node;

p3 -> val += p1 -> val;

if(p3 -> val >= 10){

p3 -> val -= 10;

node -> val = 1;

}

p1 = p1 -> next;

if(p1 == NULL && p3 -> next -> val == 0)

p3 -> next = NULL;

p3 = p3 -> next;

}

while(p2 != NULL){

struct ListNode *node = (struct ListNode *)malloc(sizeof(struct ListNode));

node -> val = 0;

node -> next = NULL;

p3 -> next = node;

p3 -> val += p2 -> val;

if(p3 -> val >= 10){

p3 -> val -= 10;

node -> val = 1;

}

p2 = p2 -> next;

if(p2 == NULL && p3 -> next -> val == 0)

p3 -> next = NULL;

p3 = p3 -> next;

}

return l3;

}