void Przerob(struct tnode** head){

    if(!*head){
        printf("Lista jest pusta!");
        return;
    }

    struct tnode* curElement = *head;
    struct tnode* nextElement = (*head)->next;

    while(nextElement != NULL){
        if(nextElement->value < 0){
            curElement->next = nextElement->next;
            free(nextElement);
            nextElement = curElement->next;
        } else {
                curElement = curElement->next;
                nextElement = curElement->next;
        }

    }

    if((*head)->value < 0){
        curElement = (*head)->next;
        free(*head);
        *head = curElement;
    }

    curElement->next = *head;

    printf("\n");

    curElement = *head;
    do{
        printf("%d ",curElement->value);
        curElement = curElement->next;
    }while(curElement != *head);

}