填加了增删改查功能却不能显示他们的功用，怎么修改啊

#include<stdio.h>#include <stdlib.h>#include <string.h>#define MAX_TICKETS 100#pragma warning(disable:4996)int main() { void add_ticket(); void delete_ticket(); void modify_ticket(); void search_ticket(); struct Ticket; int choice; do { printf("1. 添加车票"); printf("2. 删除车票"); printf("3. 修改车票"); printf("4. 查询车票"); printf("0. 退出"); printf("请输入操作编号："); scanf("%d", &choice); switch (choice) { case 1: add_ticket(); break; case 2: delete_ticket(); break; case 3: modify_ticket(); break; case 4: search_ticket(); break; case 0: printf("退出程序"); break; default: printf("无效的操作编号"); break; } } while (choice != 0); return 0; } struct Ticket { char name[50]; int id; char departure[50]; char destination[50]; int price; }; struct Ticket tickets[MAX_TICKETS]; int num_tickets = 0; void add_ticket(){//实现添加的功能 struct Ticket ticket; printf("请输入乘客姓名："); scanf("%s", ticket.name); printf("请输入车票编号："); scanf("%d", &ticket.id); printf("请输入出发地："); scanf("%s", ticket.departure); printf("请输入目的地："); scanf("%s", ticket.destination); printf("请输入车票价格："); scanf("%d", &ticket.price); tickets[num_tickets++] = ticket; printf("添加成功！\n"); } void delete_ticket() { int id; printf("请输入要删除的车票编号："); scanf("%d", &id); int index = -1; for (int i = 0; i < num_tickets; i++) { if (tickets[i].id == id) { index = i; break; } } if (index == -1) { printf("未找到该车票！\n"); } else { for (int i = index; i < num_tickets - 1; i++) { tickets[i] = tickets[i + 1]; } num_tickets--; printf("删除成功！\n"); } } void modify_ticket() { int id; printf("请输入要修改的车票编号："); scanf("%d", &id); int index = -1; for (int i = 0; i < num_tickets; i++) { if (tickets[i].id == id) { index = i; break; } } if (index == -1) { printf("未找到该车票！\n"); } else { struct Ticket ticket; printf("请输入新的乘客姓名："); scanf("%s", ticket.name); printf("请输入新的出发地："); scanf("%s", ticket.departure); printf("请输入新的目的地："); scanf("%s", ticket.destination); printf("请输入新的车票价格："); scanf("%d", &ticket.price); tickets[index] = ticket; printf("修改成功！\n"); } void search_ticket(); { int id; printf("请输入要查询的车票编号："); scanf("%d", &id); int index = -1; for (int i = 0; i < num_tickets; i++) { if (tickets[i].id == id) { index = i; } }}}

修改如下，大致改了，能运行，功能细节你自己优化吧

#include<stdio.h> 
#include <stdlib.h> 
#include <string.h> 
#define MAX_TICKETS 100 

int main() {
    void add_ticket();
    void delete_ticket();
    void modify_ticket();
    void search_ticket();
    struct Ticket;
    int choice;
    do {
        printf("1. 添加车票\n");
        printf("2. 删除车票\n");
        printf("3. 修改车票\n");
        printf("4. 查询车票\n");
        printf("0. 退出\n");
        printf("请输入操作编号：");
        scanf("%d", &choice);
        switch (choice) {
            case 1: add_ticket();
            break;
            case 2: delete_ticket();
            break;
            case 3: modify_ticket();
            break;
            case 4: search_ticket();
            break;
            case 0: printf("退出程序");
            break;
            default: printf("无效的操作编号");
            break;
        }
    }
    while (choice != 0);
    return 0;
}

struct Ticket {
    char name[50];
    int id;
    char departure[50];
    char destination[50];
    int price;
};
struct Ticket tickets[MAX_TICKETS];
int num_tickets = 0;
void add_ticket() {
    struct Ticket ticket;
    printf("请输入乘客姓名：");
    scanf("%s", ticket.name);
    printf("请输入车票编号：");
    scanf("%d", &ticket.id);
    printf("请输入出发地：");
    scanf("%s", ticket.departure);
    printf("请输入目的地：");
    scanf("%s", ticket.destination);
    printf("请输入车票价格：");
    scanf("%d", &ticket.price);
    tickets[num_tickets++] = ticket;
    printf("添加成功！\n");
}
void delete_ticket() {
    int id;
    printf("请输入要删除的车票编号：");
    scanf("%d", &id);
    int index = -1;
    for (int i = 0; i < num_tickets; i++) {
        if (tickets[i].id == id) {
            index = i;
            break;
        }
    }
    if (index == -1) {
        printf("未找到该车票！\n");
    } else {
        for (int i = index; i < num_tickets - 1; i++) {
            tickets[i] = tickets[i + 1];
        }
        num_tickets--;
        printf("删除成功！\n");
    }
}
void modify_ticket() {
    int id;
    printf("请输入要修改的车票编号：");
    scanf("%d", &id);
    int index = -1;
    for (int i = 0; i < num_tickets; i++) {
        if (tickets[i].id == id) {
            index = i;
            break;
        }
    }
    if (index == -1) {
        printf("未找到该车票！\n");
    } else {
        struct Ticket ticket;
        getchar();
        printf("请输入新的乘客姓名：");
        scanf("%s", ticket.name);
        getchar();
        printf("请输入新的出发地：");
        scanf("%s", ticket.departure);
        getchar();
        printf("请输入新的目的地：");
        scanf("%s", ticket.destination);
        printf("请输入新的车票价格：");
        scanf("%d", &ticket.price);
        tickets[index] = ticket;
        printf("修改成功！\n");
    }
    
}

void search_ticket() {
    int id;
    printf("请输入要查询的车票编号：");
    scanf("%d", &id);
    int index = -1;
    for (int i = 0; i < num_tickets; i++) {
        if (tickets[i].id == id) {
            index = i;
        }
    }
    if (index != -1)
    {
        printf("乘客姓名：%s\n", tickets[index].name);
        printf("出发地：%s\n", tickets[index].departure);
        printf("目的地：%s\n", tickets[index].destination);
        printf("车票价格：%d\n", tickets[index].price);
    }
    else
        printf("Not Found!!!");
}

你这不排版下吗