Function insert in list

Question

Hello. I am developing this function below:

void inserir_inicio (tipo_lista * p, tipo_lista * novo_no)
{
  novo_no -> prox = p;
  p = novo_no;
}

And in the main I’m calling for:

inserir_inicio(&p, cria_no(1));
imprimir_lista(p);

And when I run nothing comes out on the screen.

Would someone tell me if the in_start function is wrong?

Answer 1

In main your function starts empty(NULL), then you call the insert function and do not update the main value, then the list remains empty. If the list is not empty, you will insert at the beginning and will not update at the main which is the first, then the error continues.

What is missing is the Return:

tipo_lista * inserir_inicio (tipo_lista * p, tipo_lista * novo_no)
{
  novo_no -> prox = p;
  return novo_no;
}

And in main:

p = inserir_inicio(p, cria_no(1));
imprimir_lista(p);