main.c(负责测试）

#include <stdlib.h>
#include <stdio.h>
#include <time.h>
#include "nohead.h"
int main()
{LNode *list = NULL;struct score_st data[10],mydata,data1;int i = 0;srand((unsigned)time(NULL));//初始化数组for (i = 0; i < 10; i++){data[i].chinese = rand() % 100;data[i].english = rand() % 100;data[i].math = rand() % 100;data[i].student_id = i;snprintf(data[i].name, 32, "学生的名字是%d", i);}data1.chinese = rand() % 100;data1.english = rand() % 100;data1.math = rand() % 100;data1.student_id = 100;snprintf(data1.name, 32, "学生的名字是%d", 100);//打印链表中的数据list_display(list);//链表中插入数据，头部插入，无头节点单向不循环链表for (i = 0; i < 10; i++){list_insert(&list, &data[i]);}list_display(list);//查找id = 3的学生信息list_find(list,3,&mydata);printf("%4s %20s %4s %4s %4s\n", "学号", "姓名", "数学", "语文", "外语");printf("%4d %20s %4d %4d %4d\n", mydata.student_id,mydata.name, mydata.math, mydata.chinese,mydata.english);//删除链表中的第一个有效节点(单向不循环无头节点链表）//list_delete(&list);//list_display(list);list_insert_at(&list,0,&data1);list_display(list);list_destroy(list);
}

nohead.c(负责函数实现）

#include<stdio.h>
#include<stdlib.h>
#include "nohead.h"int list_insert_at(struct LNode **list,int i, struct score_st *data)
{struct LNode *node = *list,*newnode = NULL;int j = 0;if (i < 0){return -1;}if (i == 0){newnode = (LNode*)malloc(sizeof(LNode));if (newnode == NULL){return -3;}newnode->score = *data;newnode->next = *list;*list = newnode;return 0;}//找到第i-1个有效节点while ((j < i-1)&&(node!=NULL)){node = node->next;j++;}if (node == NULL){return -2;}newnode = (LNode*)malloc(sizeof(LNode));if (newnode == NULL){return -3;}newnode->score = *data;newnode->next = node->next;node->next = newnode;return 0;
}int list_insert(struct LNode **list, struct score_st *data)
{LNode *newnode = NULL;newnode = (LNode*)malloc(sizeof(LNode));if (newnode == NULL)return -1;newnode->score = *data;newnode->next = *list;*list = newnode;
}void list_display(LNode *list)
{LNode *ps = list;if (ps == NULL){printf("链表为空\n");return -1;}printf("学生的信息如下:\n");printf("%4s %20s %4s %4s %4s\n", "学号", "姓名", "数学", "语文", "外语");while (ps){printf("%4d %20s %4d %4d %4d\n", ps->score.student_id,ps->score.name, ps->score.math, ps->score.chinese,ps->score.english);ps = ps->next;}
}int list_find(LNode *ps,int id,struct score_st *data)
{while (ps){if (ps->score.student_id == id){*data = ps->score;return 0;}ps=ps->next;}return -1;
}//删除无头节点链表中第一个有效节点
int list_delete(LNode **ps)
{LNode* curnode = *ps;if (*ps == NULL){printf("链表为空删除失败\n");return -1;}(*ps) = curnode->next;free(curnode);return 0;
}void list_destroy(LNode *p)
{LNode *nextnode = NULL;while (p){nextnode = p->next;free(p);p = nextnode;}}

nohead.h(负责函数声明）

#ifndef NOHEAD_H__
#define NOHEAD_H__
#define MAX_SIZE 32
//定义结构体类型,保存学生成绩
struct score_st
{char name[MAX_SIZE];int student_id;int math;int chinese;int english;
};
typedef struct LNode
{struct score_st score;struct LNode *next;
}LNode;
//无头节点单向不循环链表,在链表头部插入数据,第一个有效节点的下标为0
int list_insert(struct LNode *list, struct score_st *score);
//按位置插入节点
int list_insert_at(struct LNode **list, int i, struct score_st *data);
void list_display(LNode *list);
int list_delete(LNode **ps);
void list_destroy(LNode *list);
//查找id==**的结点
int list_find(LNode *ps, int id,struct score_st *data);
#endif