use warnings;
use strict;

while (<DATA>) {
    my @ms = /[ARKYGZX]/g;
    print if @ms == 2 or @ms == 3;
}

__DATA__
AAgoodpeople
AgoodApeople
XgoodpeopleK
ARKYgoodpeopleGZX
goodpeopleGZX

##</code><code>##

AAgoodpeople
AgoodApeople
XgoodpeopleK
goodpeopleGZX