合并两个排序的链表---递归实现

题目描述

#include <stdio.h>
#include <stdlib.h>
typedef struct node
{
int value;
struct node *next;
}LinkList;

//创建带头结点的单链表
void CreateList(LinkList *L)
{
int data;
LinkList *p=NULL,*q=L;	//p指向新分配的结点，q始终指向链表的尾部
printf("input the data: ");
while(scanf("%d",&data) !=EOF)
{
p=(LinkList*)malloc(sizeof(LinkList));
p->value=data;
p->next=NULL;
q->next=p;
q=p;
}
}
LinkList *Merge(LinkList *pHead1,LinkList *pHead2)
{
if(pHead1==NULL)
return pHead2;
if(pHead2==NULL)
return pHead1;
LinkList *pMergeHead=NULL;
if(pHead1->value < pHead2->value)
{
pMergeHead=pHead1;
pMergeHead->next=Merge(pHead1->next,pHead2);
}
else
{
pMergeHead=pHead2;
pMergeHead->next=Merge(pHead1,pHead2->next);
}
return pMergeHead;
}

void output(LinkList *L)
{
LinkList *p=L;
while(p!=NULL)
{
printf("%d\t",p->value);
p=p->next;
}
}
int main()
{
LinkList *a=(LinkList*)malloc(sizeof(LinkList));
LinkList *b=(LinkList*)malloc(sizeof(LinkList));
CreateList(a);
CreateList(b);
LinkList *pHead1=a->next;
LinkList *pHead2=b->next;
output(Merge(pHead1,pHead2));
return 0;
}