2、 掌握线性表的基本操作：初始化，插入，删除，查找，判空，求线性表长度等运算在顺序存储结构和链式存储结构上的实现。

#include "stdlib.h" #define NULL 0 #define LEN sizeof(struct student) struct student { long num; struct student *next ; } ; int length; struct student *create() { struct student *head1,*p1,*p2; length=0; head1=NULL; printf("enter the list data,end with fushu :\n"); p1=(struct student*)malloc(LEN); scanf("%ld",&p1->num); p1->next=NULL; while(p1->num>=0) {++length; if(length==1) head1=p1; else p2->next=p1; p2=p1; p1=(struct student*)malloc(LEN); scanf("%ld",&p1->num); p1->next=NULL; } free(p1); return(head1); } struct student *insert(struct student *head,struct student *stud) { struct student *p0,*p1,*p2; p1=head; p0=stud; if(head==NULL) { head=p0; p0->next=NULL; } else while((p0->num>p1->num)&&(p1!=NULL)) {p2=p1; p1=p1->next; } if(head==p1) {p0->next=head; head=p0; } else {p2->next=p0; p0->next=p1; } ++length; return(head); } struct student *delete(struct student *head,long num) { struct student *p1,*p2; if(head==NULL) {printf("\nLIST NULL!!!\n"); return(head); } p1=head; while(num!=p1->num&&p1->next!=NULL) { p2=p1; p1=p1->next; } if(num==p1->num) { if(p1==head) head=p1->next; else p2->next=p1->next; printf("the delete number is:%ld\n",num); free(p1); length--; } else printf("%ld not been found!\n",num); return(head); } struct student *find(struct student *head,long num) { struct student *p1,*p2; int i; if(head==NULL) {printf("\n LIST NULL!!!\n"); return(head); } p1=head; while(num!=p1->num&&p1!=NULL) {i=1; p2=p1; p1=p1->next; i++; } if(p1!=NULL) printf("the find number is:%d\n",i); else printf("%ld not been found!\n",num); return(head); } void print(struct student *head) { struct student *p4; if(head==NULL) printf("LIST NULL!!!\n"); else printf("\n Now,these %d nodes are:\n",length); p4=head; if(head!=NULL) do { printf("%ld\n",p4->num); p4=p4->next; } while(p4!=NULL); } struct student *clear(struct student *head) { struct student *p1; int i; p1=head; if(head==NULL) { printf("\nLIST NULL!!!\n");} else for(i=1;i<=length;i++) { p1->num=0; p1=p1->next; } return(head); } void menu() { printf("\n\n\n\n\n"); printf(" |-----------------------|\n"); printf(" | Input the choose |\n"); printf(" |-----------------------|\n"); printf(" | 1--print |\n"); printf(" | 2--find |\n"); printf(" | 3--delete |\n"); printf(" | 4--insert |\n"); printf(" | 5--clear |\n"); printf(" | 0--break |\n"); printf(" |-----------------------|\n"); } void main() { struct student *head,*stud; long num1,num2; char yes_no; int in_num; head=create(); do { menu(); printf("choose the list number: "); scanf("%d",&in_num); switch(in_num) { case 1: print(head); break; case 2: {printf("\n please enter the number you want to find:\n"); scanf("%ld",&num1); find(head,num1);}; break; case 3: {printf("\n please enter the number you want to delete:\n"); scanf("%ld",&num2); head=delete(head,num2); print(head);}; break; case 4: { printf("enter the number you want to insert:\n"); stud=(struct student *)malloc(LEN); scanf("%ld",&stud->num); head=insert(head,stud); print(head);}; break; case 5: head=clear(head); print(head); break; case 0: break; default: printf("error\n"); } printf("\nchoose again?(y(Y) or n(N)) "); yes_no=getche(); printf("\n\n"); } while(yes_no=='Y' || yes_no=='y'); exit(1); }