两个链表合并C语言

解题思路:phead1 phead2来接受两个链表，phead3来合并

注意事项:

参考代码:

#include<stdio.h>
#include<stdlib.h>
struct student
{
    int num;
    struct student *pnext;
};

struct student* creat(int n)    //接受链表
{
    struct student *pnew,*pend,*phead;
    for(int i=0;i<n;i++)
    {
        pnew=(struct student*)malloc(sizeof(struct student));
        if(scanf("%d",&pnew->num));
        pnew->pnext=NULL;
        if(i==0)
        {
            phead=pnew;
            pend=pnew;
        }
        else
        {
            pend->pnext=pnew;
            pend=pnew;
        }
    }
    return phead;
}

struct student* combine(struct student *phead1,struct student *phead2)    //合并
{
    struct student *p=phead1,*q=phead2,*phead3=NULL,*ptemp;
    while(p!=NULL&&q!=NULL)    //直到p和q都结束才跳出循环
    {
        if(p->num>q->num)    //第一个if到q或p其中一个为NULL就结束了
        {
            if(phead3==NULL)
            {
                phead3=q;
                ptemp=phead3;
            }
            else
            {
                ptemp->pnext=q;
                ptemp=q;
            }
            q=q->pnext;
        }
        else
        {
            if(phead3==NULL)
            {
                phead3=p;
                ptemp=phead3;
            }
            else
            {
                ptemp->pnext=p;
                ptemp=p;
            }
            p=p->pnext;
        }
        if(q==NULL)    //剩余的一串链表
        ptemp->pnext=p;
        else
        ptemp->pnext=q;
    }
    return phead3;
}

void print(struct student *phead3)
{
    struct student *ptemp=phead3;
    while(ptemp!=NULL)
    {
        printf("%d ",ptemp->num);
        ptemp=ptemp->pnext;
    }
}

int main()
{
	int n,num;
	struct student *phead1=NULL,*phead2=NULL,*phead3=NULL;
    while(scanf("%d",&n)!=EOF)    //有多个2组
    {
        phead1=creat(n);
        if(scanf("%d",&num));
        phead2=creat(num);
        phead3=combine(phead1,phead2);
        print(phead3);
        printf("\n");    //格式，测试一次性有大量数据
    }
	return 0;
}