【数据结构】链表

#include<stdio.h>#include<malloc.h>struct node {int data;struct node *next;};struct node *head,*tail,*p;int n=0;void creatNode();int length();int outNode(int i);void insertNode(int i,int dta);void print();void delNode(int i);int isNull();void main() {int i, nodeLength;printf("初始化5个链表\n");for(i=1; i<=5; i++) {creatNode();printf("输入data：");scanf("%d", &tail->data);}//初始化完毕//求链表长度nodeLength = length();printf("链表长度为：%d\n", nodeLength);//取第三个元素printf("第三个元素为：%d\n", outNode(3));printf("在第3个元素前插入888\n");insertNode(3, 888);print();printf("删除第3个节点\n");delNode(3);print();printf("链表是否为空：%s\n", isNull()==0?"YES":"NO");}void creatNode() {struct node *p0;p0 = (struct node*)malloc(sizeof(struct node));p0->next = NULL;if(p0 == NULL) printf("ERROR!");if(head == NULL) {head = p0;tail = p0;//n ++;}tail->next = p0;tail = p0;//n ++;}int length() {int n = 1;struct node *pt;pt = head;while(pt->next != NULL){n ++;pt = pt->next;}return n;}//取出第i个个元素int outNode(int i) {int k=1;struct node *pt;pt = head;//if(i>lgh) {//printf("所寻元素超出范围\n");//return//}while(k<i) {pt = pt->next;k ++;}return  pt->data;}void print() {struct node *pt;pt = head;while(1) {printf("%d ", pt->data);if(pt->next == NULL) break;pt = pt->next;}printf("\n");}//在第i个数前面插入一个数void insertNode(int i,int dta) {struct node *pt, *pd, *da;int k=1;da = (struct node*)malloc(sizeof(struct node));da->next = NULL;da->data = dta;pt = head;while(k<i) {pd = pt;pt = pt->next;k ++;}pd->next = da;da->next = pt;}void delNode(int i) {struct node *pt, *pd;int k=1;pt = head;while(k<i) {pd = pt;pt = pt->next;k ++;}pd->next = pt->next;}int isNull() {if(head == tail)return 0;return 1;}