#include <stdio.h>
//Defining a structure of the node
struct node {
    int data;
    struct node* next;
    };

void insert (struct node* rec, int x) {
    struct node* temp = (struct node*)malloc(sizeof(struct node));
    temp->data = x;
    temp->next = NULL;
    rec = temp; // head and rec is now pointing to the same node
}

void print(struct node* rec){
    printf("%d", rec->data); //error occurs here
    puts("");
}

main(){
    struct node *head = NULL; //head is currently pointing to NULL
    insert (head, 5); //Passing the head pointer and integer 5 to insert()
    print(head);
}