-foreach my $ia (0..$#ch) {
- foreach my $ib (0..$#ch) {
- my $vab = $vab[$ia][$ib];
- my $vba = $vab[$ib][$ia];
+sub chremain () {
+ return grep { !$ch[$_]{Dropped} } (0..$#ch);
+}
+
+foreach my $ia (chremain()) {
+ $defeats->add_vertex($choices[$ia]);
+ foreach my $ib (chremain()) {
+ my $vab = scalar @{ $vab[$ia][$ib] };
+ my $vba = scalar @{ $vab[$ib][$ia] };