#include <stdio.h>
#include "hotel.h"
int main (void)
{
    int nights;
    double hotel_rate;
    int code;
   
    while ((code = menu ()) != QUIT)
    {
        switch (code)
        {
            case 1: hotel_rate = HOTEL1;
                    break;
            case 2: hotel_rate = HOTEL2;
                    break;
            case 3: hotel_rate = HOTEL3;
                    break;
            case 4: hotel_rate = HOTEL4;
                    break;
            default: hotel_rate = 0.0;
                    printf ("Oops!\n");
                    break;
        }
        nights = getnights ();
        showprice (hotel_rate, nights);
    }
    printf ("Thank you and goodbye. ");
    return 0;
}
#include <stdio.h>
#include "hotel.h"
int menu (void)
{
    int code, status;
   
    printf ("\n%s%s\n", STARS, STARS);
    printf ("Enter the number of the desired hotel: \n");
    printf ("1) Fairfield Arms 2) Hotel Olympic\n");
    printf ("3) Chertworthy Plaza 4) The Stockton\n");
    printf ("5) quit\n");
    printf ("%s%s\n", STARS, STARS);
    while ((status = scanf ("%d", &code)) != 1 || (code < 1 || code > 5))
    {
        if (status != 1)
        scanf ("%*s");
        printf ("Enter an integer form 1 to 5, please.\n");
    }
    return code;
}

int getnights (void)
{
    int nights;
   
    printf ("How many nights are needed? ");
    while (scanf ("%d", &nights)!= 1)
    {
        scanf ("%*s");
        printf ("Please enter an integer, such as 2.\n");
    }
    return nights;
}

void showprice (double rate, int nights)
{
    int n;
    double total = 0.0;
    double factor = 1.0;
   
    for (n=1; n <= nights; n++, factor *= DISCOUNT)
        total += rate * factor;
        printf ("The total cost will be $%0.2f.\n", total);
}

#define QUIT         5
#define HOTEL1         80.00
#define HOTEL2        125.00
#define HOTEL3        155.00
#define HOTAL4        200.00
#define DISCOUNT    0.95
#define STARS "*****************"

int menu (void);
int getnights (void);
void showprice (double, int);
请问这个程序怎么才能放在工程里面编译出来，我用的是free c还是说需要其他软件

好象用 #include 也可以

#include<xxx.c>
另外需要跟主程序放到同一个目录里。

主程序是main（）？

main()是主函数,在工程里main.c才是主程序。