program to implement stack using linked list

#include<stdio.h>
#include<malloc.h>
void disp();
void push(int data);
void pop();
struct node
{
    int info;
    struct node *link;

}*top=NULL;
main()
{
int ch,i,m;
while(1)
{
printf("\n..............MENU...........\n");
printf("\n1.push element\n");
printf("2.pop element\n");
printf("3.display\n");
printf("4.exit\n");
printf("enter your choice:");
scanf("%d",&ch);
switch(ch)

{
    case 1:
      printf("\nenter the element:");
    scanf("%d",&m);
    push(m);
    break;
    case 2:
    pop();
    break;
    case 3:
    disp();
    break;
    case 4:
    exit(1);
}

}

}

void push(int data)
{
    struct node *tmp;

    tmp=malloc(sizeof(struct node));
    tmp->info=data;
    tmp->link=top;
    top=tmp;
}
void pop()
{
    struct node *tmp;
    tmp=malloc(sizeof(struct node));

    if(top==NULL)
    printf("stack is empty\n");
    else
    {
      tmp=top;
      printf("popped item=%d\n",tmp->info);
        top=top->link;
        tmp->link=NULL;
        free(tmp);
    }


}
void disp()
{

    struct node *tmp;
    tmp=top;
    if(top==NULL)
    printf("stack is empty\n");
    else
    {

      printf("stack elements\n");
      while(tmp!=NULL)
      {
          printf("%d\t",tmp->info);
          tmp=tmp->link;
      }
    }
}


                    OUTPUT


..............MENU...........

1.push element
2.pop element
3.display
4.exit
enter your choice:1

enter the element:1

..............MENU...........

1.push element
2.pop element
3.display
4.exit
enter your choice:1

enter the element:2

..............MENU...........

1.push element
2.pop element
3.display
4.exit
enter your choice:1

enter the element:3

..............MENU...........

1.push element
2.pop element
3.display
4.exit
enter your choice:3
stack elements
3       2       1
..............MENU...........

1.push element
2.pop element
3.display
4.exit
enter your choice:2
popped item=3

..............MENU...........

1.push element
2.pop element
3.display
4.exit
enter your choice:2
popped item=2

..............MENU...........

1.push element
2.pop element
3.display
4.exit
enter your choice:2
popped item=1

..............MENU...........

1.push element
2.pop element
3.display
4.exit
enter your choice:2
stack is empty

..............MENU...........

1.push element
2.pop element
3.display
4.exit
enter your choice:4

Process returned 1 (0x1)   execution time : 26.988 s
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