[C Programming] Implementation of Linked List in C

#include<stdio.h>
#include<stdlib.h>

struct node {
  int data;
  struct node *next;
};

void insert_node(struct node **Head)
{
struct node *iterate;
int data;

printf("Enter node data:");
scanf("%d", &data);

if(*Head == NULL) {
*Head = (struct node*)malloc(sizeof(struct node*));
(*Head)->data = data;
(*Head)->next = NULL;
} else {
  iterate = *Head;
  while(iterate->next != NULL)
   iterate = iterate->next;
   iterate->next = (struct node*)malloc(sizeof(struct node*));
   iterate->next->data = data;
   iterate->next->next = NULL;
}
}

void show_linked_list(struct node *Head)
{
struct node *iterate = Head;

if(!iterate) {
      printf("Linked List is empty\n");
return;
}

printf("Linked List elements are\n");

while (iterate != NULL) {
     printf("%d\n", iterate->data);
 iterate = iterate->next;
}
}

void isLL_ContainLoop(struct node *Head)
{
struct node *start, *end = NULL;

start = Head;

do {
  if (start != NULL) {
  if(start->next)
 start = start->next->next;
    else
              start = start->next;
        }

        if (end == NULL)
           end = Head;
        else
           end = end->next;
}while(start != end && start!= NULL);

if (start == end && start != NULL)
  printf("+++Linked List has LOOP+++\n");
    else
  printf("+++Linked List has NO LOOP+++\n");
}

void cleanup(struct node **Head)
{
  struct node *iterate = *Head;
  while(*Head)
  {
iterate = (*Head);
*Head = (*Head)->next;
iterate->next = NULL;
free(iterate);
}
}

struct node* search_node(struct node *Head, int data)
{
  while (Head) {
  if (Head->data == data)
   return Head;
  Head = Head->next;
  }
  return NULL;
}


void delete_node(struct node **Head)
{
  struct node *del_node = NULL;
  struct node *iterate = *Head;
  int data, find;
 
  if (*Head == NULL)
  printf("Linked List is empty\n");

  show_linked_list(*Head);
  printf("Select data to delete from linked list\n");
scanf("%d", &data);

del_node = search_node(*Head, data);
if (del_node) {
  printf("Data is present\n");

    if (del_node == *Head) {
        *Head = (*Head)->next;
        iterate->next = NULL;
        free(iterate);
    } else {
  while (iterate->next != del_node)
    iterate = iterate->next;
           iterate->next = iterate->next->next;
           del_node->next = NULL;
           free(del_node);
              }

} else {
  printf("Data is not present\n");
}
}

void main()
{
struct node *Head = NULL;
int choice, data;

while(1) {
printf("****Menu*****\n");
printf("select 1: Insert new node\n");
printf("select 2: show linked list elements\n");
printf("select 3: is Linked list contain loop\n");
printf("select 4: Delete node\n");
printf("select 5: Search node\n");
printf("select 6: Exit\n");
printf("Enter your input 1-6 ?\n");
scanf("%d", &choice);

switch(choice){
case 1: insert_node(&Head); break;
case 2: show_linked_list(Head); break;
case 3: isLL_ContainLoop(Head); break;
case 4: delete_node(&Head); break;
case 5: printf("Enter Data to search in Linked List\n");
scanf("%d", &data);
if (search_node(Head, data)) printf("Data is present\n");
   else printf("Data is not present\n");
    break;
case 6:
        default: cleanup(&Head); exit(1);
}
printf("=========================\n");
    }
}

Output:
-----------
****Menu*****
select 1: Insert new node
select 2: show linked list elements
select 3: is Linked list contain loop
select 4: Delete node
select 5: Search node
select 6: Exit
Enter your input 1-6 ?
1
Enter node data:11
=========================
****Menu*****
select 1: Insert new node
select 2: show linked list elements
select 3: is Linked list contain loop
select 4: Delete node
select 5: Search node
select 6: Exit
Enter your input 1-6 ?
1
Enter node data:22
=========================
****Menu*****
select 1: Insert new node
select 2: show linked list elements
select 3: is Linked list contain loop
select 4: Delete node
select 5: Search node
select 6: Exit
Enter your input 1-6 ?
2
Linked List elements are
11
22
=========================
****Menu*****
select 1: Insert new node
select 2: show linked list elements
select 3: is Linked list contain loop
select 4: Delete node
select 5: Search node
select 6: Exit
Enter your input 1-6 ?
3
+++Linked List has NO LOOP+++
=========================
****Menu*****
select 1: Insert new node
select 2: show linked list elements
select 3: is Linked list contain loop
select 4: Delete node
select 5: Search node
select 6: Exit
Enter your input 1-6 ?
5
Enter Data to search in Linked List
22
Data is present
=========================
****Menu*****
select 1: Insert new node
select 2: show linked list elements
select 3: is Linked list contain loop
select 4: Delete node
select 5: Search node
select 6: Exit
Enter your input 1-6 ?
4
Linked List elements are
11
22
Select data to delete from linked list
11
Data is present
=========================
****Menu*****
select 1: Insert new node
select 2: show linked list elements
select 3: is Linked list contain loop
select 4: Delete node
select 5: Search node
select 6: Exit
Enter your input 1-6 ?
2
Linked List elements are
22
=========================
****Menu*****
select 1: Insert new node
select 2: show linked list elements
select 3: is Linked list contain loop
select 4: Delete node
select 5: Search node
select 6: Exit
Enter your input 1-6 ?

6