求助！怎么传递参数啊！

Question

参数没法传递。。。。head在别的函数里是空的。。。

#include<stdio.h>
#include<stdlib.h>
#include<string.h>
#include<malloc.h>
#define LEN sizeof(Student)
#include <time.h>


typedef struct SIS { //结构体的声明
    long StudentID;    //学号
    char Name[20];  //姓名
    char Sex[10];//性别
    int Age;//年龄
    char TOE[30] ;//Time of Enrollment入学日期
    float GPA;//（加权平均）
    char PhoneNo[100]; //电话号码
    char MailingAddress[100];//邮箱
    struct SIS *next;//指向下一个结构体的指针
} Student;




/////////////////////声明函数///////////////////////
void wellcome();//欢迎界面
void start();//开始界面
int menu();//菜单
SIS* input();//输入/插入
SIS* del(Student *head);//删除
int search (Student *head);//查找
int ALL(Student *head);//显示全部
///////////////////////////////////////////////////

void wellcome() { //欢迎界面
    time_t rawtime;
    struct tm * timeinfo;
    time ( &rawtime );
    timeinfo = localtime ( &rawtime );


    printf("*************************************************\n");
    printf("*\t\t学生信息管理系统\t\t*\n");
    printf("*\t\t\t\t\t\t*\n");
    printf("*\t\t\tLAB 8\t\t\t*\n");
    printf("*\t\t\t\t\t\t*\n");
    printf("*\t            莱茵出品\t\t        *\n");
    printf("*\t\t\t\t\t\t*\n");
    printf("*\t\t\t\t2.33.ver\t*\n");
    printf("*\t\t\t\t\t\t*\n");
    printf("*\t\t\t\t\t\t*\n");
    printf("*************************************************\n");
    printf("%s", asctime (timeinfo));
    printf("Please Press Enter to continue……");

}


void start() { //开始界面
    int a=0;
    int b=0;
    int A=15080121;
    getchar();
    system("cls");
    printf("\n\n\n");
    printf("\t\t学生信息管理系统\n\n\n");
    printf("\t\t\t2.33.Ver\n\n\n");
    getchar();
    system("cls");
/*  printf("\t\t请输入用户名和密码，按下Enter继续\n\n\n");
    printf("\tAdmin:");
    scanf("%d",&a);
    printf("\n");
    printf("\tPassword:");
    scanf("%d",&b);
    if(a==A&&b==A) {
        getchar();
        system("cls");
    } else {
        printf("\t\t\t您没有足够的权限！！！！！\nPlease Press Enter to EXIT……");
        getchar();
        exit(0);
    }*/
}

int menu() {//菜单
    int shuru=0;
    printf("\n\n\n");
    printf("\t\t （1）Create a student list\n");
    printf("\t\t （2）Insert a student\n");//(to the sorted array or the sorted linked list )
    printf("\t\t （3）Delete a student\n");
    printf("\t\t （4）Search a student\n");
    printf("\t\t （5）Display all students\n");
    printf("\t\t （6）exit\n");
    printf("\t\t请选择功能:");
    scanf("%d",&shuru);
    return shuru;

}





SIS* input() {//输入、插入
    Student *p1,*p2;
    Student *student;
    Student *head=NULL;
    char a = 'y';

    system("cls");

    student = (Student*) malloc (LEN);
    printf("\t请按照要求输入\n");
    while(a=='y'||a=='Y') {
        p2=p1=head;
        printf("\tStudentID：");
        scanf("%ld",&student->StudentID);
        printf("\t");
        printf("Name：");
        scanf("%s",student->Name);
        printf("\t");
        printf("Sex：");
        scanf("%s",&student->Sex);
        printf("\t");
        printf("Age：");
        scanf("%d",&student->Age);
        printf("\t");
        printf("TOE：");
        scanf("%s",&student->TOE);
        printf("\t");
        printf("GPA：");
        scanf("%f",&student->GPA);
        printf("\t");
        printf("PhoneNo：");
        scanf("%s",&student->PhoneNo);
        printf("\t");
        printf("MailingAddress：");
        scanf("%s",&student->MailingAddress);
        printf("\n\n\n\n");
        student->next=NULL;
        fflush(stdin);
        if(head==NULL)head=student;
        else {
            while(p1->StudentID<student->StudentID&&p1->next!=NULL) {
                p2=p1;
                p1=p1->next;
            }
            if(p1->StudentID>student->StudentID)
                if(p1==head) {
                    student->next=head;
                    head=student;
                } else {
                    p2->next=student;
                    student->next=p1;
                }
            else p1->next=student;
        }
        student = (Student *) malloc (LEN);
        printf("是否继续添加,输入'y'或'Y'继续\n");
        a=getchar();
        fflush(stdin);
    }
    printf("\t\t\t录入成功!\n");    free(student);
    return(p1);
}



SIS* del(Student *head) {           //删除学生信息
    Student *p1,*p2;
    int tage = 0;
    long StudentID;
    system("cls");
    p1=head;
    printf("\n\t\t请输入学号:");
    scanf("%d",&StudentID);
    if(head==NULL) {
        printf("不存在学生信息!\n");
        return 0;
    }
    while(p1!=NULL) {
        if(p1->StudentID==StudentID) {
            tage=1;
            if(p1==head)head=head->next;
            else p2->next=p1->next;
            free(p1);
            break;
        }
        p2=p1;
        p1=p1->next;
    }
    if(tage==0) printf("要删除的学生信息不存在!\n");
    tage=0;
    printf("\t\t\t成功删除息\n");
    fflush(stdin);
//  system("cls");

    return (head);
}

int search (Student *head) {      //查询
    Student *p1;
    Student *student;
    int tage = 0;
    long StudentID;

    system("cls");
    printf("请输入要查询的学生学号：");
    scanf("%d",&StudentID);
    p1=head;
    if(head==NULL) {
        printf("无学生信息!\n");
        return 0;
    } else
        while(p1!=NULL)
            if(p1->StudentID==StudentID) {
                tage=1;
                printf("你查找的学生信息如下:\n");
                printf("\t\tStudentID：%ld\n",p1->StudentID);
                printf("\t\tName：%s\n",p1->Name);
                printf("\t\tSex：%s\n",p1->Sex);
                printf("\t\tAge：%d\n",p1->Age);
                printf("\t\tTOE：%s\n",p1->TOE);
                printf("\t\tGPA：%2f\n",p1->GPA);
                printf("\t\tPhonrNo：%s\n",p1->PhoneNo);
                printf("\t\tMailingAddress：%s\n\n\n",&p1->MailingAddress);
                break;
            }


            else  p1=p1->next;
    if(tage==0)printf("\t\t\t无该学生信息!\n");
    tage=0;
    fflush(stdin);

    return 0;
}

int ALL(Student *head) { //显示全部信息
    Student *p1;
    p1 = head;
    system("cls");
    if(head==NULL) {
        printf("无学生信息!\n");
        return 0;
    }
    while(p1!=NULL) {
        printf("\t\tStudentID：%ld\n",p1->StudentID);
        printf("\t\tName：%s\n",p1->Name);
        printf("\t\tSex：%s\n",p1->Sex);
        printf("\t\tAge：%d\n",p1->Age);
        printf("\t\tTOE：%s\n",p1->TOE);
        printf("\t\tGPA：%2f\n",p1->GPA);
        printf("\t\tPhonrNo：%s\n",p1->PhoneNo);
        printf("\t\tMailingAddress：%s\n\n",p1->MailingAddress);
        p1=p1->next;
    }
    return 0;
}



main() {
    int choose;
    int x=1;
    Student *head=NULL;

    wellcome();
    start();
    while(x) {
        choose=menu();
        switch(choose) {
            case 1: {
                input();
                system("pause");
                printf("Please Press Enter to Return……");
                getchar();
                system("cls");
                break;
            }


            case 2: {
                input();
                system("pause");
                printf("Please Press Enter to Return……");
                getchar();
                system("cls");
                break;
            }


            case 3: {
                del(head);
                system("pause");
                printf("Please Press Enter to Return……");
                getchar();
                system("cls");
                break;
            }


            case 4: {
                search(head);
                system("pause");
                printf("Please Press Enter to Return……");
                getchar();
                system("cls");
                break;
            }


            case 5: {
                ALL(head);
                system("pause");
                printf("Please Press Enter to Return……");
                getchar();
                system("cls");
                break;
            }


            case 6: {
                exit(1);
            }


            default: {
                system("cls");
                printf("\n\n\n\t\t\t无此功能\n\n\n\n");
                break;
            }
        }

    }
}

Answer 1

问题能再明确点吗?。。。