@foo = ('a(b(c)d(e(f)g)h)i(j(k)l(m)n)o',
        'a(b(c)d(e(f)g)h)i(j(k)l(m)n)o');

for (@foo) {
   print "\'$_\' has ";
   while s/[(][^()][)]//;        # get rid of matched ()
   print "un" if /[()]/;         # see if any unmatched
   print "balanced parentheses"
}