train_manage_code

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

struct stack
{
    int size;
    int top;
    char **arr; // Array of strings
};

int isFull(struct stack *ptr)
{
    if (ptr->top == ptr->size - 1)
    {
        printf("TRAIN IS FULL\n");
        return -1;
    }
    return 0;
}

int isEmpty(struct stack *ptr)
{
    if (ptr->top == -1)
    {
        printf("TRAIN IS EMPTY\n");
        return 1;
    }
    return 0;
}

void push(struct stack *ptr, char *val)
{
    if (isFull(ptr))
    {
        printf("TRAIN IS ALREADY FULL, CANNOT ADD MORE PASSENGERS\n");
    }
    else
    {
        ptr->top++;
        ptr->arr[ptr->top] = (char *)malloc((strlen(val) + 1) * sizeof(char)); // Allocate memory for the string
        strcpy(ptr->arr[ptr->top], val); // Copy the passenger name
        printf("\n PASSENGER %s HAS BEEN ADDED\n", val);
    }
}

char *pop(struct stack *ptr)
{
    if (isEmpty(ptr))
    {
        printf("TRAIN IS EMPTY, YOU CAN BOOK A TICKET NOW\n");
        return NULL;
    }
    else
    {
        char *val = ptr->arr[ptr->top];
        ptr->top--;
        return val;
    }
}

char *peek(struct stack *sp, int i)
{
    int arrIndex = sp->top - i + 1;
    if (arrIndex < 0 || arrIndex > sp->top)
    {
        printf("INVALID POSITION\n");
        return NULL;
    }
    else
    {
        return sp->arr[arrIndex];
    }
}

void display(struct stack *sp)
{
    if (isEmpty(sp))
    {
        printf("TRAIN IS EMPTY, NO ONE IS IN THE TRAIN\n");
    }
    else
    {
        printf("PASSENGERS ARE:\n");
        for (int i = 0; i <= sp->top; i++)
        {
            printf("%s ", sp->arr[i]);
        }
        printf("\n");
    }
}

int main()
{
    struct stack *sp = (struct stack *)malloc(sizeof(struct stack));
    sp->size = 10;
    sp->top = -1;
    sp->arr = (char **)malloc(sp->size * sizeof(char *)); // Allocate memory for an array of strings
    char h[50];
    int option;

    do
    {
        printf("\n1. Check if train is full\n");
        printf("2. Check if train is empty\n");
        printf("3. Book a ticket\n");
        printf("4. Remove a passenger\n");
        printf("5. Last stop of this train\n");
        printf("6. Display list of train members\n");
        printf("7. Exit\n");
        printf("Enter your option: ");
        scanf("%d", &option);
        getchar(); // Clear the buffer to handle newline

        switch (option)
        {
        case 1:
            isFull(sp);
            break;
        case 2:
            isEmpty(sp);
            break;
        case 3:
            if (!isFull(sp))
            {
                printf("ENTER THE NAME OF THE PASSENGER: \n");
                fgets(h, 50, stdin);
                h[strcspn(h, "\n")] = 0; // Remove newline character from the input
                push(sp, h);
            }
            break;
        case 4:
        {
            char *passenger = pop(sp);
            if (passenger != NULL)
            {
                printf("PASSENGER %s IS LEAVING THE TRAIN\n", passenger);
                free(passenger); // Free the memory allocated for the passenger name
            }
            break;
        }
        case 5:
        {
            printf("Enter the position from the top (1 for last stop): ");
            int pos;
            scanf("%d", &pos);
            getchar(); // Clear the buffer to handle newline
            char *passenger = peek(sp, pos);
            if (passenger != NULL)
            {
                printf("Passenger at position %d: %s\n", pos, passenger);
            }
            break;
        }
        case 6:
            display(sp);
            break;
        case 7:
            printf("Jai Hind! Dhanyawad, Thank you!\n");
            break;
        default:
            printf("Error: Please enter a valid option.\n");
            break;
        }
    } while (option != 7);

    // Free allocated memory
    for (int i = 0; i <= sp->top; i++)
    {
        free(sp->arr[i]);
    }
    free(sp->arr);
    free(sp);

    return 0;
}