[C++]GM buy from shops

[BackPlayer 55]

hello guys how can i  block GM buy from private shops only(not from NPC).

[.Devil. 28]

+ Open shop.cpp
+ Search for CShop::Buy(LPCHARACTER ch, BYTE pos)
+ After:

if (pos >= m_itemVector.size())

	    {

	        sys_log(0, "Shop::Buy : invalid position %d : %s", pos, ch->GetName());

	        return SHOP_SUBHEADER_GC_INVALID_POS;

	    }

put:

if (IsPCShop() && ch->GetGMLevel() > GM_PLAYER)

	        return SHOP_SUBHEADER_GC_SOLD_OUT;

I haven't tested it but should work.