Linked list: insert a node in the head

take head Declare as a global variable

#include<iostream>

using namespace std;

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

Node* head;// take head Declare as a global variable 

void Insert(int x)
{
	 Node* temp = new Node; 
	 temp -> data = x;
	 temp -> next = head;
	 head = temp;
}

void Print()
{
	 Node* temp = head;
	 printf("List is: ");
	 while(temp != NULL)
	 {
	 	printf(" %d",temp -> data);
	 	temp = temp -> next;
	 }
	 printf("\n");
}



int main()
{
	head = NULL; 
	printf("How many numbers?\n");
	
	int n, x;
	scanf("%d",&n);
	
	for(int i = 0; i < n; i++)
	{
		printf("Enter the number \n");
		scanf("%d",&x);
		Insert(x);
		Print();
	}
	
	return 0;
}

  take head Defined as a local variable （Insert Function pass value ）

#include<iostream>

using namespace std;

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


Node* Insert(Node* head, int x)
{
	 Node* temp = new Node; 
	 temp -> data = x;
	 temp -> next = head;
	 head = temp;
	 return temp;
}

void Print(Node* head)
{
	 printf("List is: ");
	 while(head != NULL)
	 {
	 	printf(" %d",head -> data);
	 	head = head -> next;
	 }
	 printf("\n");
}



int main()
{
	Node* head = NULL; 
	printf("How many numbers?\n");
	
	int n, x;
	scanf("%d",&n);
	
	for(int i = 0; i < n; i++)
	{
		printf("Enter the number \n");
		scanf("%d",&x);
		head = Insert(head, x);
		Print(head);
	}
	
	return 0;
}

   take head Defined as a local variable （Insert Function address ）

#include<iostream>

using namespace std;

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


Node* Insert(Node** pointerToHead, int x)
{
	 Node* temp = new Node; 
	 temp -> data = x;
	 temp -> next = *pointerToHead;
	 *pointerToHead = temp;

}

void Print(Node* head)
{
	 printf("List is: ");
	 while(head != NULL)
	 {
	 	printf(" %d",head -> data);
	 	head = head -> next;
	 }
	 printf("\n");
}



int main()
{
	Node* head = NULL; 
	printf("How many numbers?\n");
	
	int n, x;
	scanf("%d",&n);
	
	for(int i = 0; i < n; i++)
	{
		printf("Enter the number \n");
		scanf("%d",&x);
		Insert(&head, x);
		Print(head);
	}
	
	return 0;
}