STACK USING LINKED LIST

/*
********************************
********************************
****STACK USING LINKED LIST ****
********************************
********************************
*/
#include<stdio.h>
#include<conio.h>
#include<malloc.h>
typedef struct node {
    int data;
    struct node *next;
}node;
node *top;
void push() {
    node *p;
    int x;
    p=(node *)malloc(sizeof(node));
    printf("enter the data \t\n");
    scanf("%d",&x);
    p->data=x;
    p->next=top;
    top=p;
}
void pop() {
    int x;
    node *p;
    p=top;
    top=p->next;
    x=p->data;
    printf("THE POPPED ELEMENT IS %d ", x);
    free(p);
}
void display() {
    node *p;
    p=top;
    while(p!=NULL) {
        printf("\t%d",p->data);
        p=p->next;
    }
}
main() {
    int i;
    do{
    printf("\n1.PUSH\n2.POP\n3.DISPLAY\n4.EXIT");
    scanf("%d",&i);
    switch(i) {
    case 1:
        push(); break;
    case 2:
        pop(); break;
    case 3:
        display(); break;

    }
}while(i!=4);
    getch();
}