# gcc -g -Wall -o cprog cprog_test.c

before="$(date +%s)"

./cprog

after="$(date +%s)"
elapsed_seconds="$(expr $after - $before)"
echo Elapsed seconds for code block: $elapsed_seconds

# -----

# gcc -framework Foundation cprog_test.m -o objcprog

before="$(date +%s)"

./objcprog

after="$(date +%s)"
elapsed_seconds="$(expr $after - $before)"
echo Elapsed seconds for code block: $elapsed_seconds

// cprog_test.c

#include <stdio.h>
#include <errno.h>
#include <sys/types.h>

static  int  addOne (int i)
{
   return (i+1);
}

int main (int argc, char *argv[])
{
   int  i = 0;
   while (i<1000000000)
      i = addOne (i);
   printf ("Done in C!\\n");
   
   return (0);
}

// cprog_test.m

#import <Foundation/Foundation.h>

@interface CounterClass : NSObject
{
   // no need
}

- (int)addOne:(int)i;

@end

@implementation CounterClass

- (int)addOne:(int)i
{
   return (i+1);
}

@end

int main (int argc, const char * argv[])
{
   int  i = 0;

   NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
   
   CounterClass  *counter = [[CounterClass alloc] init];
   
   while (i<1000000000)
      i = [counter addOne:i];
   printf ("Done in ObjC!\\n");

   [counter release];
   [pool drain];

   return (0);
}

static  int  addOne (int i)
{
   if (i)  {
      int  j = i * 2;
      
      i = i + 2;
      if (j)
         i = i - 1;
      j = j / 2;
      if (j)
         i = i - 1;      
   }
   
   return (i+1);
}

- (int)addOne:(int)i
{
   if (i)  {
      int  j = i * 2;
      
      i = i + 2;
      if (j)
         i = i - 1;
      j = j / 2;
      if (j)
         i = i - 1;      
   }
   
   return (i+1);
}

gcc -o MojProgram MojProgram.c

#include<iostream>
using namespace std;

class Element // definicija klase Element koja cini element liste
{
 public:
  int key;
  Element* prev ;
  Element* next ;
  Element(int key) // konstruktor
  {
    this->key = key;
    prev = NULL; // pokazivac na prethodni clan liste
    next = NULL; // pokazivac na sljedeci clan liste
  }
};

class DLList
{
 protected:
  Element* head;
  Element* tail;

 public:
  DLList () // konstruktor liste
  {
     head = NULL;
     tail = NULL;
  }
  ~DLList() // destructor liste
  {
    Element* tmp = head;
    while (tmp = NULL)
    {
           Element* tmpDelete = tmp;
           tmp = tmp->next;
           delete tmpDelete;
    }
    head=tail=NULL;
  }

  void insert(int k) // ubacivanje elementa na pocetak liste
  {
    Element *node = new Element(k);
    head->prev=&k;
    k->next=&head;
    k->prev=NULL;
  }


  Element* search(int k) // -- pretraživanje elementa s ključem k u listi
  {
      Element *tmp = head;
      
      while (tmp != NULL)
      {
             if (tmp->key == k)
             {
                 return tmp;
             }
             tmp = tmp->next;
      }
      return NULL;
  }

  void Delete(int k) // procedura koja briše prvi element iz liste s kljucem k
  {
      Element *tmp = head;
      
      while (tmp != NULL)
      {
             if (tmp->key == k)
             {
                 delete tmp;
             }
             tmp = tmp->next;
      }
      return;
  }

  void print() // procedura za ispis elemenata liste
  {
     Element *tmp = head;
     cout << head << " ---> " ;
     while (tmp != NULL)
     {
            cout << "|" << tmp->key << "|" << tmp->next << " ---> ";
            tmp = tmp->next;
     }
     cout << endl;
     return;
  }

  void printReverse() // procedura za obrnuti ispis elemenata liste
  {
     Element* tmp1 = tail;
     cout << tail << " ---> " ;
     while (tmp1 != NULL)
     {
            cout << "|" << tmp1->key << "|" << tmp1->prev << " ---> ";
            tmp1 = tmp1->prev;
     }
     cout << endl;
     return;
  }

  void deleteList() // brisanje cijele liste
  { 
      head=tail=NULL;
  }

  bool empty() // provjeri je li lista prazna
  {
     int counter = 0;

     Element* tmp = head;
     while (tmp != NULL)
     {
            counter++;
            tmp = tmp->next;
     }
     if (counter == 0)
     {
         return 1;
     }else
      {
          return 0;
      }
  }

  unsigned int size() // funkcija koja vraca trenutni broj elemenata u listi
  {
    int counter = 0;
    Element* tmp = head;

    while (tmp != NULL)
    {
           counter ++;
           tmp = tmp->next;
    }
    return counter;
  }
};

int main()
{
  DLList Lista;

  Lista.insert(2);
  Lista.insert(17);
  Lista.insert(99);
  Lista.insert(20);
  Lista.insert(34);
  Lista.insert(24);

  cout << "Ispis liste: " << endl;
  Lista.print();

  cout << "Ispis liste od zadnjeg elementa prema prvom: " << endl;
  Lista.printReverse();

  cout << "U listi ima " << Lista.size() << " elemenata. " << endl;

  if (Lista.empty()==1)
  {
      cout << "Lista je prazna." << endl;
  }else
   {
       cout << "Lista nije prazna." << endl;
   }

return 1;
}

/scriptrunner4/sr_Temp_17081437094d83e42462e91: In member function 'void DLList::insert(int)':
/scriptrunner4/sr_Temp_17081437094d83e42462e91:45: error: cannot convert 'int*' to 'Element*' in assignment
/scriptrunner4/sr_Temp_17081437094d83e42462e91:46: error: base operand of '->' is not a pointer
/scriptrunner4/sr_Temp_17081437094d83e42462e91:47: error: base operand of '->' is not a pointer

#include<iostream>
using namespace std;

class Element // definicija klase Element koja cini element liste
{
 public:
  int key;
  Element* prev ;
  Element* next ;
  Element(int _key) : key(_key) // konstruktor
  {
    prev = NULL; // pokazivac na prethodni clan liste
    next = NULL; // pokazivac na sljedeci clan liste
  }
};

class DLList
{
 protected:
  Element* head;
  Element* tail;

 public:
  DLList () // konstruktor liste
  {
     head = NULL;
     tail = NULL;
  }
  ~DLList() // destructor liste
  {
    Element* tmp = head;
    while (tmp != NULL)
    {
           Element* tmpDelete = tmp;
           tmp = tmp->next;
           delete tmpDelete;
    }
    head=tail=NULL;
  }

  void insert(int k) // ubacivanje elementa na pocetak liste
  {
    Element *node = new Element(k);
    if(head == NULL) 
    { 
	head = node;
    }
    else
    {
	head->prev=node;
    	node->next=head;
    	node->prev=NULL;
    	head = node;
    }

    if(tail == NULL) tail = head;
    if(tail->prev == NULL && tail != head) tail->prev = head;
  }


  Element* search(int k) // -- pretraživanje elementa s ključem k u listi
  {
      Element *tmp = head;
      
      while (tmp != NULL)
      {
             if (tmp->key == k)
             {
                 return tmp;
             }
             tmp = tmp->next;
      }
      return NULL;
  }

  void Delete(int k) // procedura koja briše prvi element iz liste s kljucem k
  {
      Element *tmp = head;
      
      while (tmp != NULL)
      {
             if (tmp->key == k)
             {
		 if(tmp->prev != NULL) tmp->prev->next = tmp->next;
		 if(tmp->next != NULL) tmp->next->prev = tmp->prev;
                 
		 delete tmp;
		 return;
             }
             tmp = tmp->next;
      }
    
  }

  void print() // procedura za ispis elemenata liste
  {
     Element *tmp = head;

     while (tmp != NULL)
     {
            cout << "|" << tmp->key << "|";
            tmp = tmp->next;
     }
     cout << endl;
     return;
  }

  void printReverse() // procedura za obrnuti ispis elemenata liste
  {
     Element* tmp1 = tail;
    
     while (tmp1 != NULL)
     {
            cout << "|" << tmp1->key << "|";
            tmp1 = tmp1->prev;
     }
     cout << endl;
     return;
  }

  void deleteList() // brisanje cijele liste
  { 
    Element* tmp = head;
    while (tmp != NULL)
    {
           Element* tmpDelete = tmp;
           tmp = tmp->next;
           delete tmpDelete;
    }
    head=tail=NULL;
  }

  bool empty() // provjeri je li lista prazna
  {
     return (head == NULL) ? 1 : 0;
  }

  unsigned int size() // funkcija koja vraca trenutni broj elemenata u listi
  {
    int counter = 0;
    Element* tmp = head;

    while (tmp != NULL)
    {
           counter ++;
           tmp = tmp->next;
    }
    return counter;
  }
};

int main()
{
  DLList Lista;

  Lista.insert(2);
  Lista.insert(17);
  Lista.insert(99);
  Lista.insert(20);
  Lista.insert(34);
  Lista.insert(24);

  cout << "Ispis liste: " << endl;
  Lista.print();

  cout << "Ispis liste od zadnjeg elementa prema prvom: " << endl;
  Lista.printReverse();

  cout << "U listi ima " << Lista.size() << " elemenata. " << endl;

  if (Lista.empty())
  {
      cout << "Lista je prazna." << endl;
  }else
   {
       cout << "Lista nije prazna." << endl;
   }

return 0;
}

Element(int _key) : key(_key) // konstruktor

 if(tmp->prev != NULL) tmp->prev->next = tmp->next;
 if(tmp->next != NULL) tmp->next->prev = tmp->prev;