Print linked list in reverse order - C Program

#include<stdio.h>
#include<stdlib.h>
struct node
{
     int data;
     struct node *next;
}*head;

void insert_data(int value)
{
     struct node *var,*temp;
     temp=head;
     var=(struct node *)malloc(sizeof(struct node));
     var->data=value;
     if(head==NULL)
     {
          head=var;
          head->next=NULL;
     }
     else
     {
          while(temp->next!=NULL)
          {
               temp=temp->next;
          }
          var->next=NULL;
          temp->next=var;
     }
}
void reverse_list()
{
     struct node *temp,*temp1,*var;
     temp=head;
     var=NULL;
     while(temp!=NULL)
     {
          temp1=var;
          var=temp;
          temp=temp->next;
          var->next=temp1;
     }
     head=var;
}
void display()
{
     struct node *var;
     var=head;
     printf("list of elements: \n");
     while(var!=NULL)
     {
          printf("-> %d ",var->data);
          var=var->next;
     }
}
int main()
{
     int i,value,n=1;
     char ch='y';
     head=NULL;
     printf("\tMenu");
     printf("\n-----------------------\n");
     printf(" 1. Insert node");
     printf("\n 2. Display the list of node");
     printf("\n 3. Reverse the nodes");
     printf("\n 4. Exit");
     //printf("\n-----------------------");
     while(ch=='y')
     {
          printf("\n\nChoose Operation: ");
          scanf("%d",&i);
          switch(i)
          {
               case 1 :
                    printf("\nEnter element in node %d: ",n);
                    scanf("%d",&value);
                    insert_data(value);
                    display();
                    n++;
               break;
               case 2 :
                    display();
               break;
               case 3 :
                    printf("\nReverse order ");
                    reverse_list();
                    display();
               break;
               case 4 :
                    exit(0);
               default:
                    printf("\nInvalid Operation!! Choose valid operation..");
               break;
          }
     }
     return 0;
}