Add Two Numbers

题意：
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
比如：
数字3 4 2 +
数字4 6 5 =
数字8 0 7

#include <stdlib.h>#include <stdio.h>typedef struct _LinkNode{    int data;    struct _LinKNode *next;}LinkNode;typedef struct _Linklist{    LinkNode *head;    int length;}Linklist;typedef struct _Student{    int id;}Student;//初始化Linklist* Init(){    Linklist *list=(Linklist*)malloc(sizeof(Linklist));    LinkNode *node=(LinkNode*)malloc(sizeof(LinkNode));    list->length=0;    list->head=node;    node->next=NULL;    return list;}//插入void Push(Linklist* list,int pos,int data){    //合法性检验    if(list==NULL||pos<0)        return;    if(pos > list->length)        pos=list->length;    //创建辅助接点    LinkNode *pCurrent=list->head;    //创建新节点    LinkNode *newnode=(LinkNode*)malloc(sizeof(LinkNode));    newnode->data=data;    //遍历找到插入节点的位置    int i;    for( i=0;i<pos;i++)        pCurrent=pCurrent->next;    //插入新节点    newnode->next=pCurrent->next;    pCurrent->next=newnode;    list->length++;}void Print(Linklist *list){    LinkNode *pCurrent;    //合法性检验    if(list==NULL)        return;    //创建辅助接点    pCurrent=list->head->next;    int i;    //遍历打印    for( i=0;i<list->length;i++)    {        printf("%2d",pCurrent->data);        pCurrent=pCurrent->next;    }}void Add(Linklist *s1,Linklist *s2,Linklist *s3){    if(s1==NULL && s2==NULL)    //创建辅助节点    LinkNode *pCurrent1;    pCurrent1=s1->head->next;    LinkNode *pCurrent2;    pCurrent2=s2->head->next;    //c为进位，sum为两数相加的和，data为除去进位的数    int c=0;    int sum=0;    int data=0;    while(pCurrent1!=NULL&&pCurrent2!=NULL)    {        sum=pCurrent1->data+pCurrent2->data+c;        c=sum/10;        data=sum%10;        Push(s3,s3->length,data);        pCurrent1=pCurrent1->next;        pCurrent2=pCurrent2->next;    }    //head->1->2->3->NULL   head->2->3->NULL    while(pCurrent1!=NULL)    {        sum=pCurrent1->data+c;        c=sum/10;        data=sum%10;        Push(s3,s3->length,data);        pCurrent1=pCurrent1->next;    }    //head->1->2->NULL   head->1->2->3->NULL    while(pCurrent2!=NULL)    {        sum=pCurrent2->data+c;        c=sum/10;        data=sum%10;        Push(s3,s3->length,data);        pCurrent2=pCurrent2->next;    }    //head->4->2->9->NULL   head->1->2->3->NULL    if(c>0)    {       Push(s3,s3->length,c);    }}int main(){    //创建链表初始化    Linklist *list1=Init();    Linklist *list2=Init();    //插入数据    Push(list1,0,3);    Push(list1,0,4);    Push(list1,0,2);    Push(list2,0,4);    Push(list2,0,6);    Push(list2,0,9);    Push(list2,0,7);    Push(list2,0,5);    //打印    Print(list1);    printf("\n");    Print(list2);    //两链表相加    Linklist *list3=Init();    Add(list1,list2,list3);    //打印    printf("\n");    Print(list3);    return 0;}