链表的增删排序等操作

#include <stdio.h>#include <malloc.h>typedef struct Node{int data;//数据域 Node * pNext; //指针域 }NODE,*PNODE;//NODE等价于struct Node,PNODE等价于struct Node *PNODE create_list();//创建链表 void show_list(PNODE);//打印链表 int getSize(PNODE);//得到链表长度void delete_list(PNODE);//删除链表bool is_empty(PNODE);//判断是否为空 void insert_list(PNODE);//插入一个元素 void sort_list(PNODE);//对链表进行排序 int main(void){PNODE pHead;pHead = create_list(); show_list(pHead); delete_list(pHead);show_list(pHead); insert_list(pHead);show_list(pHead); sort_list(pHead);show_list(pHead); return 0; }//创建链表 PNODE create_list(){printf("请输入你要创建的链表的元素个数\n");printf("Len=");int len;scanf("%d",&len);PNODE pHead = (PNODE)malloc( sizeof(NODE) );if(pHead == NULL){printf("分配失败，程序终止.");exit(-1); } PNODE pTail = pHead;//令尾指针等于头指针 pTail->pNext = NULL; PNODE p = pTail; int i,val; for(i=0; i<len; i++){printf("请输入第%d个元素的值:",i+1);scanf("%d",&val); p = (PNODE)malloc( sizeof(NODE) );        p->data = val;p->pNext = NULL; pTail->pNext = p;pTail = p; }     return pHead; } //打印链表 void show_list(PNODE pHead){if(is_empty(pHead) ){ printf("链表为空,不能打印元素\n");return; }printf("\n该链表共有%d个元素\n",getSize(pHead) ); PNODE p = pHead->pNext; while(p != NULL){printf("%d ",p->data);p = p->pNext; } printf("\n"); } //得到链表长度int getSize(PNODE pHead){if(is_empty(pHead) ){ return 0; }int count=0; PNODE p = pHead->pNext; while(p != NULL){count++; p = p->pNext; }return count; }//判断是否为空bool is_empty(PNODE pHead){if(pHead==NULL || pHead->pNext==NULL){return true; } return false; } //删除链表 void delete_list(PNODE pHead){if(is_empty(pHead) ){ printf("链表为空，不能删除\n");return; }int size =  getSize(pHead); printf("\n该链表共有%d个元素\n", size); printf("请输入要删除第几个元素:");int index;scanf("%d",&index);while( index<1 || index > size){printf("你输入的值超过界限，请重新输入:");scanf("%d",&index); } int i; PNODE p = pHead; PNODE temp; for(i=0; i<size; i++){if( i == index-1 ){temp = p->pNext; p->pNext = p->pNext->pNext;free(temp); //把删除的节点释放,防止内存泄露 } p = p->pNext; }} //插入一个链表void insert_list(PNODE pHead){ if(is_empty(pHead) ){ printf("链表为空，不能删除\n");return; }int size =  getSize(pHead); printf("\n该链表共有%d个元素\n", size); printf("请输入要插入为第几个元素 元素值:");int index,val;scanf("%d %d",&index,&val);while( index<1 || index > size+1){printf("你输入的值超过界限，请重新输入:");scanf("%d",&index); }int i; PNODE p = pHead; //第一种插入的算法 /*for(i=0; i<=size; i++){//因为是插入,所以可以i=size if( i == index-1 ){PNODE temp = (PNODE)malloc( sizeof(NODE) );temp->data = val; temp->pNext = p->pNext; p->pNext = temp;} p = p->pNext; }*///第二种插入的算法 i=0; while(p!=NULL && i < index-1){p = p->pNext;i++; }PNODE temp = (PNODE)malloc( sizeof(NODE) );temp->data = val; temp->pNext = p->pNext; p->pNext = temp;} //对链表进行排序void sort_list(PNODE pHead){if(is_empty(pHead)){printf("链表为空,排序失败"); return; } printf("\n链表排序的结果如下:\n");int i,j,t;PNODE p,q; int len=getSize(pHead);for(i=0,p=pHead->pNext; i<len-1; i++,p=p->pNext){for(j=i+1,q=p->pNext; j<len; j++,q=q->pNext){if(p->data > q->data){//相当于数组的: a[i] > a[j]t = p->data;      //相当于数组的: t = a[i];p->data = q->data;//相当于数组的: a[i] = a[j];q->data = t;      //相当于数组的: a[j] = t;} } } }