-
-{
- foreach my $islandname (sort keys %{ $route_mysteries{$oceanname} }) {
- warn "$route_mysteries{$oceanname}{$islandname} routes".
- " for unknown island $islandname\n";
- }
-
- my $allroutes= $routes{$oceanname};
-
- my @propqueue= ();
-
- sub distance_set_propagate ($$$$) {
- my ($lev, $start, $upto, $start2upto) = @_;
- $allroutes->{$start}{$upto}= $start2upto;
- push @propqueue, [ $lev, $start, $upto ];
- }
-
- sub distance_propagate_now {
- my ($lev, $start, $upto) = @_;
- my $startref= $allroutes->{$start};
- my $start2upto= $startref->{$upto};
- my $uptoref= $allroutes->{$upto};
-
- for my $next (keys %$uptoref) {
- next if $next eq $upto;
- my $unext= $uptoref->{$next};
- next unless defined $unext;
- distance_update("${lev}p", $start, $next, $start2upto + $unext);
- }
- }
-
- sub distance_update ($$$$) {
- my ($lev, $x, $y, $newdist) = @_;
- distance_update_one("${lev}x",$x,$y,$newdist);
- distance_update_one("${lev}y",$y,$x,$newdist);
- }
-
- sub distance_update_one ($$$$) {
- my ($lev, $x, $y, $newdist) = @_;
- my $xref= $allroutes->{$x};
- my $currently= $xref->{$y};
- return if defined($currently) and $currently <= $newdist;
- distance_set_propagate("${lev}o",$x,$y,$newdist);
- }
-
- foreach my $xn (keys %$allroutes) {
- my $routes= $allroutes->{$xn};
- distance_set_propagate('0', $xn, $xn, 0);
- foreach my $yn (keys %$routes) {
- distance_set_propagate('0', $yn, $yn, 0);
- distance_set_propagate('X', $xn, $yn, $routes->{$yn});
- distance_set_propagate('Y', $yn, $xn, $routes->{$yn});
- }
- }
- my $ref;
- while ($ref= shift @propqueue) {
- distance_propagate_now(@$ref);
- }
-
- db_doall(<<END)
- DELETE FROM dists;
-END
- ;
- my $sth= $dbh->prepare(<<'END')
- INSERT INTO dists VALUES
- ((SELECT islandid FROM islands WHERE islandname == ?),
- (SELECT islandid FROM islands WHERE islandname == ?),
- ?);
-END
- ;
- foreach my $xn (keys %$allroutes) {
- my $routes= $allroutes->{$xn};
- foreach my $yn (keys %$routes) {
- $sth->execute($xn, $yn, $routes->{$yn});
- }
- }
- $dbh->commit();
-
- # select ia.islandname, ib.islandname,dists.dist from dists, islands as ia on dists.aiid = ia.islandid, islands as ib on dists.biid = ib.islandid order by ia.islandname, ib.islandname;
-}