#ifndef _LIST_H

#define _LIST_H

#include <iostream.h>

template <class Type>
class List
{
  private:
    class Linkable
    {
      private:
        Type dat;
        Linkable *follower;
      public:
        Linkable(Type d) {dat=d;follower=0;}
        ~Linkable(void) { if(follower) delete follower; }
        linkto(Linkable *n) {follower=n;}
        Linkable *next(void) {return follower;}
        Type & data(void) {return dat;}
    };
    Linkable *first;
    Linkable *last;
    int length;

  public:
    List(void) {first=last=0;length=0;}
    ~List(void) {if(first) delete first;}
    clear() {if(first) delete first;length=0;first=last=0;}
    int len(void) {return length;}
    listappend(Type d)
    {
      Linkable *n = new Linkable(d);
      if(!first)
      {
        first = last = n;
      } else {
        last->linkto(n);
        last=n;
      }
      length++;
    }
    int listdelete(int i)
    {
      int j;
      Linkable *cur, *f;
      if(i<0 || i>=length)
        return 0;
      if(i==0)
      {
        f = first;
        first = first->next();
        delete f;
      } else {
        for(j=0,cur=first ; j<i-1 ; j++ , cur=cur->next());
        f = cur->next();
        cur->linkto(f->next());
        if(last==f)
          last = f->next();
        delete f;
      }
      length--;
      return 1;
    }
    Type & operator[](int i)
    {
      int j;
      Linkable *cur;
      if(i<0 || i>=length)
        {cerr << "List index "<<i<<" out of bounds (E_RANGE)\n";exit(1);}
      for(j=0,cur=first ; j<i ; j++ , cur=cur->next());
      return cur->data();
    }
    int in(const Type d)
    {
      int j=0;
      Linkable *cur=first;
      for(; (cur)&&(cur->data()!=d); cur=cur->next(), j++);
      return j<length ? j : 0;
    }
};

#endif