利用链表来实现对员工信息的存储，排序，删除，插入

这个问题很简单，但是它涉及的面很广，所以很具有学习的意义。

#include<stdio.h>
#include<string.h>
#include<stdlib.h>
struct Emplyee
{
    int num;
    char name[20];
    int age;
    struct Emplyee * next;
};
void main()
{
    struct Emplyee * Create();
    void Output(struct Emplyee *);
    struct Emplyee * Sort(struct Emplyee *);
    struct Emplyee * Insert(struct Emplyee *, struct Emplyee *);
    struct Emplyee * Delete(struct Emplyee *, char name[20]);
    struct Emplyee * s = Create();
    Output(s);
    printf("排序后的结果为：\n");
    s = Sort(s);
    Output(s);
    struct Emplyee my = { 21, "John", 24 };
    printf("插入后的结果为:\n");
    s = Insert(s, &my);
    Output(s);
    printf("删除后的结果为：\n");
    s = Delete(s, "John");
    Output(s);
    getchar();
}
struct Emplyee * Create()
{
    struct Emplyee  * s;
    struct Emplyee * p = NULL;
    printf("输入三个员工的名字：\n");
    for (int i = 0; i < 3; i++)
    {
        s = (struct Emplyee *)malloc(sizeof(struct Emplyee));
        s->num = i;
        gets(s->name);
        s->age = 21 + i;
        if (p == NULL)
        {
            s->next = NULL;
            p = s;
        }
        else
        {
            s->next = p;
            p = s;
        }
    }
    return p;
}
void Output(struct Emplyee * sl)
{
    while (sl)
    {
        printf("工号：%d\t姓名：%s\t年龄：%d\n", sl->num, sl->name, sl->age);
        sl = sl->next;
    }
}
struct Emplyee * Sort(struct Emplyee * s)
{
    struct Emplyee  temp, *last, *first, *p = s;
    for (int i = 0; i < 3; i++)
    {
        p = s;
        for (int j = 0; j<i; j++)
        {
            p = p->next;
        }
        first = p;
        struct Emplyee * min = p;
        while (p!= NULL)
        {
            if (p->age <min->age)
            {
                min = p;
            }
            p = p->next;
        }
        temp = *min;
        min->age = first->age;
        min->num = first->num;
　　　　strcpy(min->name,first->name);
        first->age = temp.age;
        first->num = temp.num;
　　　　strcpy(first->name,temp.name);
    }
    return s;
}
struct Emplyee * Insert(struct Emplyee * s, struct Emplyee * t)
{
    struct Emplyee * p = NULL;
    struct Emplyee * q = s;
    while ((q->age < t->age) && q->next != NULL)
    {
        p = q;
        q = q->next;
    }
    if (t->age<=q->age)//说明不是在尾部插入
    {
            if (s == q)//链表是空的
            {
                p = t;
                p->next = NULL;
            }
            else
            {
                p->next = t;
            }
        t->next = q;
    }
    else//说明是在尾部进行插入
    {
        q->next = t;
        t->next = NULL;
    }
    return s;
}
struct Emplyee * Delete(struct Emplyee * s, char name[20])
{
    struct Emplyee * p1 = NULL, *p2 = NULL;
    p1 = s;
    while ((strcmp(p1->name, name)) && p1->next != NULL)
    {
        p2 = p1;
        p1 = p1->next;
    }
    if (!(strcmp(p1->name, name)))
    {
        if (p1 == s)
        {
            s = p1->next;
        }
        else
        {
            p2->next = p1->next;
        }
        //free(p1);这个可能是编译器的问题，我只要使用，编译器就会提示我触动了断点，而事实上，我并未打任何断点。
    }
    return s;
}