1. How to auto assign the room number and print the room number for those who booked the room successfully?
2. How to check room availability?

3. How to get the data/values from the struct?

   I stuck here, don't know how to continue. Can anyone please help? Here is my code.

#include <stdio.h>

int i=0,option,room,week;
int A1_I,A1_L,A1_M,A1_G;
int A1_I_rate,A1_L_rate;
int A1_rate=400, A1_I_rate=4-0,A1_L_rate=20;
int total_room, total_I,total_L, I_week, L_week,grand_total;

struct booking{
char name[100];
int SID[100];
char sex;
int room;
}b[3];

void Main_Menu(){
//variable here : option
printf("\n1 Room Booking\n2 Room Availability\n3 Cancel Booking\n4 Payment Details\nPlease enter your option:");
scanf("%i",&option);}

void book(){
printf("\n============== Room Booking ===============\n");
printf("\nEnter your details please.\nName:");
scanf("%s",b[1].name);
printf("\nStudent ID:");
scanf("%i",b[i].SID);
//variable here : sex
printf("\nM for male, F for female\nGender:");
scanf("%s",&b[1].sex);
//variable here : room
printf("\n1 Single room\n2 Double bedded room\n3 Three bedded room\n4 Four bedded room\nPlease enter your option:");
scanf("%i",&b[1].room);
printf("\nHow many weeks to book for?\n");
scanf("%i",&week);
printf("\n==========================================\n");}

//printf("\n==========================================\n");}

void bill(){
total_room=A1_rateweek;
total_L = A1_L_rateL_week;
total_I = A1_I_rate*I_week;
grand_total=total_room+total_L+total_I;
printf("\n==========================================\n");
printf("\nThank you for booking with us. Here is your bill.");
printf("\n\nWeekly rate for the room\t: RM%i\n%i weeks of subscription\t\t: RM%i\nWeekly rate for the laundry\t: RM20\n%i weeks of subscription\t\t: RM%i\nWeekly rate for the Internet: RM%i\n%i weeks of subscription\t\t: RM%i\nTotal amount payable is RM%i.\n",A1_rate,week,total_room,L_week,total_L,A1_I_rate,I_week,total_I,grand_total);
printf("\n==========================================\n");}

int main(){
printf("\n========== Welcome to Wisdom College Hostel Management System ===========\n");
Main_Menu();
switch(option){
case 1:
for(i=0;i<3;i++){
book();

Internet:
  printf("\nDo you want to subscribe for Internet?\n1 Yes\n2 No\nPlease enter your option:");
  scanf("%i",&A1_I);
  if(A1_I==1){
    A1_I_rate=40;
    printf("How many weeks to subscribe for?\n");
    scanf("%i",&I_week);
    goto Laundry;}
  if(A1_I==2){
    A1_I_rate=0;
    goto Laundry;}
  else{
    goto Internet;}
  
Laundry:
  printf("\nDo you want to subscribe for Laundry?\n1 Yes\n2 No\nPlease enter your option:");
  scanf("%i",&A1_L);
  if(A1_L==1){
    printf("How many weeks to subscribe for?\n");
    scanf("%i",&L_week);
    goto Meal;}
  if(A1_L==2){
    A1_L_rate=0;
    goto Meal;}
  else{
    goto Laundry;}

Meal:
  printf("\nDo you want to subscribe for Meal?\n1 Yes\n2 No\nPlease enter your option:");
  scanf("%i",&A1_M);
  if(A1_M==1){
    printf("\nSorry. This service is not available for subscription.\n");
    goto Gym;}
  if(A1_M==2){
    goto Gym;}
  else{
    goto Meal;}
Gym:
  printf("\nDo you want to subscribe for Gym?\n1 Yes\n2 No\nPlease enter your option:");
  scanf("%i",&A1_G);
  if(A1_G==1){
    printf("\nSorry. This service is not available for subscription.\n");
    bill();
    break;}
  if(A1_G==2){
    bill();}
  else{
    goto Gym;}
bill();
printf("\n============== Room Details ===============\n");
printf("Name:%c\nStudent ID:%i\nGender:%s\nBlock:\nRoom Number:%i\n");
  break;}}}