Linked List

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

struct node
{
    int x;
    node *ptr;
};

node *ptr2, *ptr3;

int main()
{
    int t, i, j, k, l, a, b, c, d, y, z, n;
    char ch;

    ptr2 = 0, ptr3 = 0;
    ptr2 = (node *)malloc(sizeof(node));
    ptr2->ptr = 0;
    ptr3 = ptr2;
    ptr2->x = 10;


    scanf("%d", &t);
    getchar();
    for (i = 1; i <= t; i++)
    {
        ch = getchar();
        if (ch == 100)
        {
            if (ptr3->ptr == 0) puts("Queue Empty");
            else
            {
                printf("%d\n", ptr3->x);
                ptr3 = ptr3->ptr;
                getchar();
            }
        }
        else
        {
            scanf("%d", &d);
            ptr2->ptr = (node *)malloc(sizeof(node));
            ptr2->x = d;
            ptr2 = ptr2->ptr;
            ptr2->ptr = 0;
            getchar();
        }
    }
}