#include <stdio.h>
#include <stdlib.h>
//#include "stringVec.h"

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

struct stringVec {
   struct node* head;
};

void sv_init (struct stringVec* v);
int sv_size (struct stringVec *v);
int sv_add (struct stringVec* v, char* s);
char* sv_get (struct stringVec* v, int idx);	
void sv_remove (struct stringVec* v, int idx);
void clear (struct node* n);
struct node* findLast (struct node* n);

void sv_init (struct stringVec* v){
   v = (struct stringVec*) malloc (sizeof (struct stringVec));
   v->head = NULL;
}

int sv_size (struct stringVec* v){
   int size = 0;
   struct node* n = v->head;
   while (n != NULL){
      size ++;
      n = n->next;
   }
   return size;
}

int sv_add (struct stringVec* v, char* s){
   int size = sv_size(v);
   struct node* n;
   struct node* n2 = (struct node*) malloc (sizeof(struct node));
   n2->key = s;
   if (v->head == NULL)
      v->head = n2;
   else{
      n = v->head;
      while (n->next != NULL)
         n = n->next;
      n->next = n2;
   }
   return (size-1);      
}

char* sv_get (struct stringVec* v, int idx){
   struct node* n = v->head;
   int i;
   int size = sv_size(v);
   if (idx < size){
      for (i = 0; i < idx; i ++)
         n = n->next;
      return (n->key);
   }
   return NULL;
	
}

void sv_remove (struct stringVec* v, int idx){
   struct node* n = v->head;
   struct node* m;
   int i;
   int size = sv_size(v);
   if (idx < size){
      for (i = 0; i < idx-1; i ++)
         n = n->next;
      m = n->next;
      n->next = m->next;
      free (m);
   }
}

void clear (struct node* n){
   if (n->next == NULL)
      free (n);
   else
      clear (n->next);
}

struct node* findLast (struct node* n){
   if (n == NULL)
      return n;
   return (findLast (n->next));
}

int main() {
        char a[6] = "Hello";
        struct stringVec v;
        sv_init(&v);
        printf("%d\n", sv_size(&v)); // outputs: 0
        printf("%d\n", sv_add(&v, "First string")); // outputs: 0
        printf("%d\n", sv_add(&v, "Second string")); // outputs: 1
        printf("%d\n", sv_add(&v, "Third string")); // outputs: 2
        printf("%d\n", sv_size(&v)); // outputs: 3
        printf("%s\n", sv_get(&v, 1)); // outputs: Second string
        sv_remove(&v, 1);
        printf("%s\n", sv_get(&v, 1)); // outputs: Third string
        printf("%d\n", sv_size(&v)); // outputs: 2
        sv_add(&v, a);
        a[2] = '$';
        printf("%s\n", sv_get(&v, 2)); // outputs: Hello
        printf("%s\n", a); // outputs: He$lo
        sv_remove(&v, 0); // removes one element
        sv_remove(&v, 0); // removes one element
        sv_remove(&v, 0); // removes one element
        sv_remove(&v, 0); // nothing happens, the data structure is empty
        printf("%d\n", sv_size(&v)); // outputs: 0
        return 0;
}