stack implementation using linked list in c

#include <bits/stdc++.h>  
using namespace std; 
struct Node { 
    int data; 
    struct Node* link; 
}; 
struct Node* top; 
void push(int data) //Insert at beginning
{   struct Node* temp; 
    temp = new Node(); 
    if (!temp) { 
        cout << "\nHeap Overflow"; exit(1); 
    } 
    temp->data = data; 
    temp->link = top; 
    top = temp; 
} 
int isEmpty() 
{     return top == NULL; }  
int peek() 
{ 
    if (!isEmpty()) 
        return top->data; 
    else
        exit(1); 
}   
void pop() 
{   struct Node* temp; 
    if (top == NULL) { 
        cout << "\nStack Underflow" << endl; 
        exit(1); 
    } 
    else { 
        temp = top; 
        top = top->link;  
        temp->link = NULL; 
        free(temp); 
    } 
} 
void display()  
{   struct Node* temp; 
    if (top == NULL) { 
        cout << "\nStack Underflow"; 
        exit(1); 
    } 
    else { 
        temp = top; 
        while (temp != NULL) { 
            cout <<  temp->data << " "; 
            temp = temp->link; 
        } } } 
int main() 
{   push(11); push(22);  push(33); push(44); 
    display(); 
    cout << "\nTop element is %d\n" <<  peek(); 
    pop(); pop(); 
    display(); 
    cout << "\nTop element is %d\n" << peek(); 
    return 0; 
} 

/*
 * C Program to Implement a Stack using Linked List
 */
#include <stdio.h>
#include <stdlib.h>
 
struct node
{
    int info;
    struct node *ptr;
}*top,*top1,*temp;
 
int topelement();
void push(int data);
void pop();
void empty();
void display();
void destroy();
void stack_count();
void create();
 
int count = 0;
 
void main()
{
    int no, ch, e;
 
    printf("\n 1 - Push");
    printf("\n 2 - Pop");
    printf("\n 3 - Top");
    printf("\n 4 - Empty");
    printf("\n 5 - Exit");
    printf("\n 6 - Dipslay");
    printf("\n 7 - Stack Count");
    printf("\n 8 - Destroy stack");
 
    create();
 
    while (1)
    {
        printf("\n Enter choice : ");
        scanf("%d", &ch);
 
        switch (ch)
        {
        case 1:
            printf("Enter data : ");
            scanf("%d", &no);
            push(no);
            break;
        case 2:
            pop();
            break;
        case 3:
            if (top == NULL)
                printf("No elements in stack");
            else
            {
                e = topelement();
                printf("\n Top element : %d", e);
            }
            break;
        case 4:
            empty();
            break;
        case 5:
            exit(0);
        case 6:
            display();
            break;
        case 7:
            stack_count();
            break;
        case 8:
            destroy();
            break;
        default :
            printf(" Wrong choice, Please enter correct choice  ");
            break;
        }
    }
}
 
/* Create empty stack */
void create()
{
    top = NULL;
}
 
/* Count stack elements */
void stack_count()
{
    printf("\n No. of elements in stack : %d", count);
}
 
/* Push data into stack */
void push(int data)
{
    if (top == NULL)
    {
        top =(struct node *)malloc(1*sizeof(struct node));
        top->ptr = NULL;
        top->info = data;
    }
    else
    {
        temp =(struct node *)malloc(1*sizeof(struct node));
        temp->ptr = top;
        temp->info = data;
        top = temp;
    }
    count++;
}
 
/* Display stack elements */
void display()
{
    top1 = top;
 
    if (top1 == NULL)
    {
        printf("Stack is empty");
        return;
    }
 
    while (top1 != NULL)
    {
        printf("%d ", top1->info);
        top1 = top1->ptr;
    }
 }
 
/* Pop Operation on stack */
void pop()
{
    top1 = top;
 
    if (top1 == NULL)
    {
        printf("\n Error : Trying to pop from empty stack");
        return;
    }
    else
        top1 = top1->ptr;
    printf("\n Popped value : %d", top->info);
    free(top);
    top = top1;
    count--;
}
 
/* Return top element */
int topelement()
{
    return(top->info);
}
 
/* Check if stack is empty or not */
void empty()
{
    if (top == NULL)
        printf("\n Stack is empty");
    else
        printf("\n Stack is not empty with %d elements", count);
}
 
/* Destroy entire stack */
void destroy()
{
    top1 = top;
 
    while (top1 != NULL)
    {
        top1 = top->ptr;
        free(top);
        top = top1;
        top1 = top1->ptr;
    }
    free(top1);
    top = NULL;
 
    printf("\n All stack elements destroyed");
    count = 0;
}