Problem has been solved. Here is the solving:
Code:
STRING* c_sifre(STRING* yazi)
{
	STRING* temp = "#100";
	STRING* cozuldu = "#100";
	char* karakter;
	var a = 1;
	var deger = str_len(yazi)/3;
	var sayi;
	
	karakter = malloc(sizeof(char)*(deger+1));

	while(a<=deger)
	{
		str_cpy(temp,yazi);
		str_trunc(temp,3*(deger-a));
		sayi = str_to_num(temp);
		karakter[a] = c_alfabe(sayi);
		str_clip(yazi,3);
		a++;	
	}
	
	str_cpy(cozuldu, _str(karakter));
	
	return cozuldu;
}


Problem is solved by Quadraxas. Thanks to him...


The Life Game is disgustingly bad but the graphics and reality are extremely cool...