You'd pass in your destination node instead of desired length, and your first test would be whether you're starting at your destination. So:
sub find_path {
my ($start_at, $end_at, $been_there) = (@_, {});
if ($start_at == $end_at) {
return [$start_at];
}
else {
my @try_these = grep { ! $been_there->{$_} } @{$adjacency_list{$st
+art_at}};
return map {
my @cdr_list = find_path($_, $end_at, {%$been_there, $start_at =
+> 1});
map [$start_at, @$_], @cdr_list;
} @try_these;
}
}
Homework?
Caution: Contents may have been coded under pressure.
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