public OnPlayerCommandText(playerid, cmdtext[])
{
    if (strcmp("/help", cmdtext, true, 5) == 0)
    {
    SendClientMessage(playerid, YELLOW, "It is very simple,");
    SendClientMessage(playerid, YELLOW, "The more you kill, the more money you earn to buy weapons.");
    SendClientMessage(playerid, YELLOW, "Use /buygun to buy a weapon.");
    return true;
    }
    if (strcmp("/buygun", cmdtext, true) == 0)
    {
    SendClientMessage(playerid, YELLOW, "Use - /buygun [weaponname]");
    SendClientMessage(playerid, YELLOW, "baseballbat - $50 | sdpistol - $200 | deagle - $500 | mp5 - $600");
    SendClientMessage(playerid, YELLOW, "ak47 - $1250 | m4 - $1500 | Sniper Rifle - $2000");
    return true;
    }
    return false;
}

{

if(dialogid == dialog_buy)//Kupovina guna, dijalog 100
{
	if(response)
  		  {
      	  if(listitem == 0)//M4
   	      {
	  	  GivePlayerWeapon(playerid, 31, 150);
		  GivePlayerMoney(playerid, -600);
	  	  return 1;
 	      }
	  	  if(listitem == 1)//AK-47
	      {
		  GivePlayerWeapon(playerid, 30, 150);
		  GivePlayerMoney(playerid, -600);
		  return 1;
		  }
   		  if(listitem == 2)//Deagle
	      {
		  GivePlayerWeapon(playerid, 24, 50);
		  GivePlayerMoney(playerid, -300);
		  return 1;
		  }
		  if(listitem == 3)//Shotgun
		  {
		  GivePlayerWeapon(playerid, 25, 50);
		  GivePlayerMoney(playerid, -600);
		  return 1;
		  }
		  if(listitem == 4)//Uzi
		  {
		  GivePlayerWeapon(playerid, 32, 150);
		  GivePlayerMoney(playerid, -400);
		  return 1;
		  }
		  if(listitem == 5)//Tec9
		  {
		  GivePlayerWeapon(playerid, 29, 150);
		  GivePlayerMoney(playerid, -400);
		  return 1;
		  }
		  if(listitem == 6)//Granata
		  {
		  GivePlayerWeapon(playerid, 16, 1);
		  GivePlayerMoney(playerid, -50);
		  return 1;
		  }
		  if(listitem == 7)//Smokebang
		  {
		  GivePlayerWeapon(playerid, 17, 1);
		  GivePlayerMoney(playerid, -50);
		  return 1;
		  }
  }