View difference between Paste ID: LhxFNSfk and ZV5MCid6

 #include<iostream>
 using namespace std;
 void push(int x);
 
 typedef struct alvi
 {
     int data;
 
     struct alvi *next;
     struct alvi *prev;
 }node;
 node *head=NULL;
 
 int main()
 {
     push(1);
     push(2);
     push(3);
     return 0;
 }
 void push(int x)
 {
     node *newNode = new node();
     newNode->data = x;
     if(head==NULL)
     {
         cout<<"First node pushed"<<endl;
         newNode->prev=NULL;
         newNode->next=NULL;
         head=newNode;
     }
     else
     {
         cout<<"other node pushed"<<endl;
         newNode->prev=NULL;
         newNode->next=head;
         head= newNode;
     }
 }