add, subtract

I haven't did any coding over 4-5 years now. Anyways I decided to start working on my gamemode again. I used to have an include to add, subtract, divide, multiply stocks. Does anyone has this include? I have to find all the plugins and includes but since the main forum is down everything is hard to find. Thanks.

subtract(cash, amount[1])

stock GivePlayerCash(playerid, amount[]) {

	static cash[256];

	GetPVarString(playerid, "pMoney", cash, 256);

	if(strfind(amount, "-") == 0) SetPVarString(playerid, "pMoney", subtract(cash, amount[1]));

	else SetPVarString(playerid, "pMoney", add(cash, amount));

	return 1;

}