#al mg={#ac +mg;#var $grp= ;group;#in markgrp (1000) #ac -mg}
#ac >-mg ^     $1={#print;#if (("$1"?" "==0) && ("$1"!="A")) {#mar $1=bold cyan;#var $grp=("$1"+" "+$grp)}}


using the alias >mg<, all group members are marked bold cyan