new mp_buytime
new Float:m_flRoundCount

public plugin_init()
{
       register_event( "HLTV", "Event_HLTV_NewRound", "a", "1=0", "2=0" )
       Event_HLTV_NewRound()
       
       mp_buytime = get_cvar_pointer( "mp_buytime" )
}

public Event_HLTV_NewRound()
{
       m_flRoundCount = get_gametime()
}

if( floatround( get_pcvar_float( mp_buytime ) * 60.0 ) < get_gametime() - m_flRoundCount )
{
       // 购买武器时间完结!
}