#include <stdio.h>
#include <stdlib.h>
#include <string.h>

struct node
{
  node* next;
  char* key;
};

struct list
{
  node* first;
  int size;
};

list* createList()
{
  list* l = (list*)malloc(sizeof(list));
  l->first = NULL;
  l->size = 0;
  return l;
}

node* createNode(char *k)
{
  node* n = (node*)malloc(sizeof(node));
  n->next = NULL;
  n->key = k;
  return n;
}

void addFirst(list* l, char* key)
{
  node* x = createNode(key);
  if (l->size == 0)
  {
    l->first = x;
  }
  else
  {
    x->next = l->first;
    l->first = x;
  }
  l->size++;
}

void deleteList(list* l)
{
    node* p = l->first;
    node* temporary;
    while (p->next!=NULL)
    {
        temporary=p->next;
        p->key=NULL;
        p->next=NULL;
        l->size--;
        free(p);
        p=temporary;
    }
    l->size=0;
    l->first=NULL;
    free(l);
}

void showList(struct list* l)
{
    node* p = l->first;
    while (p!=NULL)
    {
        printf("%s ",p->key);
        p=p->next;
    }
}

void copyPlus(struct list* l,char *ch)
{
    node* p = l->first;
    addFirst(l,ch);
    while (p!=NULL)
    {
        int len1=strlen(p->key);
        int len2=strlen(ch);
        char * cat = (char*)malloc(len1+len2+1);
        strcpy(cat,p->key);
        strcat(cat,ch);
        cat[len1+1] = '\0';
        printf("[%s] \n",cat);
        addFirst(l,cat);
        printf("{%s} \n",l->first->key);
        p=p->next;
    }
}

int main(void)
{
    struct list *A=createList();
    addFirst(A,"1");
    addFirst(A,"2");
    addFirst(A,"4");
    copyPlus(A,"3");
    printf("=%s= \n",A->first->key); //this one works!
    printf("=%s= \n",A->first->next->key);
    printf("=%s= \n",A->first->next->next->key);
    showList(A);
    deleteList(A);
}