#include <stdio.h> #include <stdlib.h> typedef struct node { int val; struct node *next; }node; void insert(node *a, int val); int main(void) { node *n = NULL; insert(n, 3); printf("%i", n -> val); } void insert(node *a, int num) { node *b = malloc(sizeof(node)); b -> val = num; b -> next = NULL; a = b; }