首先建立一个链表，每个节点包括学号、姓名、性别、年龄；然后输入一个学号，如果链表中的节点包括该学号，

#include
#include
#include

struct STU
{
char number[20];
char name[20];
int sex; //0表示女 1表示男
int age;
struct STU *next_stu;
};

struct STU *creat_stu();
struct STU *delete_stu(struct STU *head, struct STU *before, struct STU *temp);

int main(void)
{
char str[20];
struct STU *head, *temp, *before;

head = creat_stu();
printf("需要查找的学号为:");
scanf("%s", str);
before = temp = head;
while (temp != NULL)
{
if (strcmp(temp->number, str) == 0)
{
printf("找到该学生，学号:%s、姓名:%s、性别：%s、年龄:%d\n",
temp->number, temp->name, temp->sex==0?"女":"男", temp->age);
head = delete_stu(head, before, temp);
printf("删除该学生完成\n");
break;
}
before = temp;
/*********Found************/
temp = temp->next_stu;//这里需要将temp指向下一个结点
}

if(NULL == temp)
{
printf("没有找到该学生\n");
}
return 0;
}

struct STU *creat_stu()
{
struct STU *p, *before, *head;
int temp;

p = before = head = NULL;
printf("请输入一个学生，以回车分开\n");
while(1)
{
p = (struct STU *)malloc(sizeof(struct STU));
printf("学号：");
scanf("%s", p->number);
printf("姓名：");
scanf("%s", p->name);
printf("性别（女填0，男填1)：");
scanf("%d", &p->sex);
printf("年龄：");
scanf("%d", &p->age);

if (before != NULL)
{
before->next_stu = p;
}
else
{
head = p;
}

printf("是否继续输入？(是的话输入1，不是的话输入0):");
scanf("%d", &temp);
if (0 == temp)
{
/*********Found************/
p->next_stu = NULL;//纠结了半天不知道这里的作用是什么，最后才知道，如果结束输入，需要将当前结点p指向的下一结点赋值为空；
break;
}
before = p;
}

return head;
}

struct STU *delete_stu(struct STU *head, struct STU *before, struct STU *temp)
{
if (temp == head)
{
/*********Found************/
head = head->next_stu;//如果删除的是头结点，则将头结点赋值为头结点指向的下一结点
free(temp);//这是内存释放
}
else
{
/*********Found************/
before->next_stu = temp->next_stu;//如果非头结点，则直接将要删除结点的前驱结点赋值为删除结点指向的下一结点
free(temp);//释放内存
}

return head;
}

#include
#include
#include

struct STU
{
char number[20];
char name[20];
int sex; //0表示女 1表示男
int age;
struct STU *next_stu;
};

struct STU *creat_stu();
struct STU *delete_stu(struct STU *head, struct STU *before, struct STU *temp);

int main(void)
{
char str[20];
struct STU *head, *temp, *before;

head = creat_stu();
printf("需要查找的学号为:");
scanf("%s", str);
before = temp = head;
while (temp != NULL)
{
if (strcmp(temp->number, str) == 0)
{
printf("找到该学生，学号:%s、姓名:%s、性别：%s、年龄:%d\n",
temp->number, temp->name, temp->sex==0?"女":"男", temp->age);
head = delete_stu(head, before, temp);
printf("删除该学生完成\n");
break;
}
before = temp;
/*********Found************/
temp = temp->next_stu;//////
}

if(NULL == temp)
{
printf("没有找到该学生\n");
}

return 0;
}

struct STU *creat_stu()
{
struct STU *p, *before, *head;
int temp;

p = before = head = NULL;
printf("请输入一个学生，以回车分开\n");
while(1)
{
p = (struct STU *)malloc(sizeof(struct STU));
printf("学号：");
scanf("%s", p->number);
printf("姓名：");
scanf("%s", p->name);
printf("性别（女填0，男填1)：");
scanf("%d", &p->sex);
printf("年龄：");
scanf("%d", &p->age);

if (before != NULL)
{
before->next_stu = p;
}
else
{
head = p;
}

printf("是否继续输入？(是的话输入1，不是的话输入0):");
scanf("%d", &temp);
if (0 == temp)
{
/*********Found************/
p->next_stu = NULL;/////////
break;
}
before = p;
}

return head;
}

struct STU *delete_stu(struct STU *head, struct STU *before, struct STU *temp)
{
if (temp == head)
{
/*********Found************/
head = temp->next_stu;//////////
}
else
{
/*********Found************/
before->next_stu = temp->next_stu;////////
}

return head;
}