Question

A bus has 28 seats, arranged in 7 rows and 4 columns:

This seating arrangement is mapped, row-wise, to a 1D-array of size 28:

0	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27

Implement a well-structured C program to enable a user to make and cancel seat reservations for the bus. The program uses a text-file seats.txt to store the reservation information: 0 indicates that a seat is not reserved, and 1 indicates that a seat is reserved. Originally all seats are not reserved:

0      0       0       0 0       0       0       0 0       0       0       0 0       0       0       0 0       0       0       0 0       0       0       0 0       0       0       0

Your program starts by initializing a 1D-array with the current contents of the seats.txt file. It must then display the following menu:

1. Display number of available seats.

2. Display seat status for all seats.

3. Reserve seat(s).

4. Delete reservation(s).

5. Exit.

Please select your choice:

Your program must loop as long as option 5 has not been selected. It must display an appropriate error message if an invalid choice is entered. After executing each of the options 1 to 4, your program must pause and display the message: “Press Enter key to continue . . .”. Your program must display the above menu after pressing the Enter keyThe options must have the following behaviors:

Option 1: Display number of available seats

It displays the current number of available seats. It then waits for the Enter key to be pressed before returning control to the main menu.

If four seats are reserved, for example, hen the output is:

Option 2: Display seat status for all seats

It displays the status of each seat. The option then waits for the Enter key to be pressed before returning control to the main menu.

Option 3: Reserve seat(s)

It displays the status of each seat.

It displays the number of available seats.

If there are no available seats, the message: “Sorry, there are no available seats.” is displayed:   

If there is one or more available seats, it prompts the user for and reads the number of required reservations. If the number of required reservations is more than the number of available seats, the message: “Error: Insufficient available seats.” is displayed:

If the number of required reservations is zero or negative, the error message: “Error: Invalid number of seats.” Is displayed:

If the required number of reservations is valid and sufficient, the program prompts for and reads the seat number

and checks that the seat number is valid and does the reservation. If the seat number is not valid or already reserved, it displays a message and asks again for the seat until all seats are reserved.

If the reservation is successful, the message: “Required seats successfully reserved” is displayed:

Options 4 . Delete reservation(s)

It displays the available seats if any.

It prompts for and reads the number of seats whose reservations are to be deleted.

If the number of seats whose reservations are to be deleted is not valid, the error message: “Error: Invalid number of reservations to delete.” Is displayed:   

If the number of seats whose reservations are to be deleted is valid, the program prompts for and reads the seat number of each seat whose reservation is to be deleted, the program prompts for the seat numbers and does the necessary validation as in reservation part.

If the deletion is successful, the message: “Required reservation(s) successfully deleted” is displayed:

Whether the update operation was done or not, control is returned to the main menu after pressing the Enter key.

Options 5. Exit

It terminates the program and writes the updated array into the seats.txt file.

Answer 1

Please refer to screenshots

Code Screenshots:

#include <stdio.h> int arr[28]; // array to store seat status 5 6 // function to show menu void show menu() { printf("1. Display number of available seats.\n"); printf("2. Display seat status of all seats.\n"); printf("3. Reserve Seat(s).\n"); printf("4. Delete Reservation(s).\n"); printf("5. Exit.\n"); 16 // function to count available seats int display_available() { int cnt = 0; int i; for (i = 0; i < 28; i++) { cnt t= (arr[i] == 0); 19 return cnt; 26 // function to show seat status void seat status() { int i; for(i = 0; i < 28; i++) { printf("Seat Ssd: %s\n", i, ((arr[i] =0)?"Available": "Reserved"));

34 // function to write final status to file seats.txt void write_status() { int i; FILE* file = fopen("seats.txt", "w"); for(i = 0; i < 28; i++) { fprintf(file, "%d\n", arr[i]); 43 // function to reserve seats void reserve_seats() { int cnt = display available(); printf("Available Seats %d\n", cnt); seat_status(); // checking if seats available if(cnt == 0){ printf("Sorry, there is no available seats\n"); return; printf("Enter number of seats required\n"); int req; scanf("%d", &req); // taking number of seats of reserved if (req > cnt) { printf("Error: Insufficient available seats. \n"); return; 63 // checking validity of seat number if (req = 0){ printf("Error: Invalid number of seats\n"); return; } F

int i; // reserving seats for(i = 0; i < req; i++) { int seat; while(1) { printf("Enter seat number\n"); scanf("%d", &seat); if(seat > && seat < 28 && arr[seat] = 0){ arr[seat] = 1; break; printf("Seat $d not available\n", seat); printf("Required seats successfully reserved\n"); void delete_reservation() { int cnt = display_available(); printf("Enter number of reservation deleted\n"); int req; scanf("%d", &reg); 95 96 // checking validity of number of seats if (req > 28 - cnt | req = 0){ printf("Error: Invalid number of reservation to delete\n"); return; } 97 98 F

100 101 104 105 106 107 108 109 110 111 112 int i; // deleting seat reservation for(i = 0; i < req; i++){ int seat; while(1) { printf("Enter seat number to delete\n"); scanf("%d", &seat); if(seat > 0 && seat < 28 && arr[seat] = 1){ arri seat] = 0; break; printf("Invalid seat number\n"); 113 114 115 116 117 printf("Required reservation(s) successfully is deleted\n"); L}

119 120 121 122 // driver function Çint main() { int i; 124 125 126 // reading from file FILE* file = fopen("seats.txt", "r"); for(i = 0; i < 28; i++) { fscanf(file, "%d", Sarr[i]); 127 F 128 129 130 while(1) { show_menu(); int ch; scanf("%d", &ch); if(ch == 1) { int cnt = display available(); printf("Available Seats are d\n", cnt); } else if (ch == 2) { seat status(); } else if (ch == 3){ reserve_seats(); } else if (ch == 4){ delete_reservation(); } else if(ch == 5){ write_status(); break; } else { printf("Invalid Choice Entered\n"); continue; 146 147 148 149 150 151 152 return 0;

Output

4. Delete Reservation(s). 5. Exit. Seat 6: Available Seat 1: Available Seat 2: Reserved Seat 3: Available Seat 4: Reserved Seat 5: Available Seat 6: Available Seat 7: Available Seat 8: Available Seat 9: Available Seat 10: Available Seat 11: Available Seat 12: Reserved Seat 13: Available Seat 14: Available Seat 15: Reserved Seat 16: Available Seat 17: Available Seat 18: Available Seat 19: Available Seat 20: Available Seat 21: Available Seat 22: Available Seat 23: Available Seat 24: Available Seat 25: Reserved Seat 26: Available Seat 27: Available 1. Display number of available seats. 2. Display seat status of all seats. 3. Reserve Seat(s). 4. Delete Reservation(s). 5. Exit. Enter number of reservation deleted Enter seat number to delete 25 Required reservation(s) successfully is deleted 1. Display number of available seats. 2. Display seat status of all seats. 3. Reserve Seat(s). 4. Delete Reservation(s). 5. Exit.

Code to copy

#include <stdio.h>

int arr[28];

void show_menu(){
   printf("1. Display number of available seats.\n");
   printf("2. Display seat status of all seats.\n");
   printf("3. Reserve Seat(s).\n");
   printf("4. Delete Reservation(s).\n");
   printf("5. Exit.\n");
  
}

int display_available(){
   int cnt = 0;
   int i;
   for(i = 0; i < 28; i++){
       cnt += (arr[i] == 0);
   }
  
}

void seat_status(){
   int i;
   for(i = 0; i < 28; i++){
       printf("Seat %d: %s\n", i, ((arr[i] == 0)?"Available":"Reserved"));
   }
}

void write_status(){
   int i;
   FILE* file = fopen("seats.txt", "w");
   for(i = 0; i < 28; i++){
       fprintf(file, "%d\n", arr[i]);
   }
}

void reserve_seats(){
   int cnt = display_available();
   printf("Available Seats %d\n", cnt);
   seat_status();
   if(cnt == 0){
       printf("Sorry, there is no available seats\n");
       return;
   }
  
   printf("Enter number of seats required\n");
   int req;
   sacnf("%d", &req);
   if(req > cnt){
       printf("Error: Insufficient available seats.\n");
       return;
   }
  
   if(req <= 0){
       printf("Error: Invalid number of seats\n");
       return;
   }
  
   int i;
   for(i = 0; i < req; i++){
       int seat;
       while(1){
           printf("Enter seat number\n");
           scanf("%d", &seat);
           if(seat > 0 && arr[seat] == 0){
               arr[seat] = 1;
               break;
           }
           printf("Seat %d not available\n", seat);
       }
   }
  
   printf("Required seats successfully reserved\n");
  
}

void delete_reservation(){
   int cnt = display_available();
   printf("Enter number of reservation deleted\n");
   int req;
   scanf("%d", &req);
   if(req > 28 - cnt || req <= 0){
       printf("Error: Invalid number of reservation to delete\n");
       return;
   }
  
   int i;
   for(i = 0; i < req; i++){
       int seat;
       while(1){
           printf("Enter seat number to delete\n");
           scanf("%d", %seat);
           if(seat > 0 && arr[seat] == 1){
               arr[seat] = 0;
           }
          
           printf("Invalid seat number\n");
       }
   }
  
   printf("Required reservation(s) successfully is deleted\n");
}

int main(){
  
   int i;
   FILE* file = fopen("seats.txt", "r");
   for(i = 0; i < 28; i++){
       fscanf(file, "%d", &arr[i]);
   }
  
   while(1){
       show_menu();
       int ch;
       scanf("%d", &ch);
       if(ch == 1){
           int cnt = display_available();
           printf("Available Seats are %d\n", cnt);
       } else if(ch == 2){
           seat_status();
       } else if(ch == 3){
           reserve_seats();
       } else if(ch == 4){
           delete_reservation();
       } else if(ch == 5){
           write_status();
           break;
       } else {
           printf("Invalid Choice Entered\n");
           continue;
       }
   }
  
  
   return 0;
}