local players = {}
local welcome_back = {}

function OnSpawn(pUnit, Event)
  pUnit:RegisterEvent("CheckForPlayers", 2000, 0)
end

function CheckForPlayers(pUnit)
    for place,plr in pairs(pUnit:GetPlayersInRange()) do
        if plr ~= nil then
            if pUnit:GetDistanceYards(plr) < 10 then
                for plce,plrs in pairs(players) do
                    if plrs ~= plr:GetName() then
                        pUnit:SendChatMessage(12,0,"Welcome To The Alliance Mall "..pPlayer:GetName().."!")
                        table.insert(players, plr:GetName())
                    else
                        for plc, plas in pairs(welcome_back) do
                            if plas ~= plr:GetName() then
                                pUnit:SendChatMessage(12,0,"Welcome back "..pPlayer:GetName().."!")
                                table.insert(welcome_back, plr:GetName())
                            end
                        end
                    end
                end
            end
        end
    end
end

RegisterUnitEvent(80051, 18, "OnSpawn")