37 lines
780 B
Perl
37 lines
780 B
Perl
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use 5.20.0;
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use experimental qw/ signatures postderef smartmatch /;
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use List::AllUtils qw/ sum max first_index min/;
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my @elements = map { chomp; [ split '/' ] } <>;
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use DDP;
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my $inv_length = 1E99;
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my $max = 0;
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build_bridge(0,0,@elements);
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say $max;
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sub build_bridge( $sofar = 0, $connector = 0, @left ) {
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for my $i ( 0..$#left ) {
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next unless $connector ~~ $left[$i]->@*;
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my @copy = @left;
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my $i = splice @copy, $i, 1;
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my $next_con = $i->[ 1 - first_index { $_ == $connector } @$i ];
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build_bridge( $sofar + sum( @$i ), $next_con, @copy );
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}
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return if @left > $inv_length;
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if( @left == $inv_length ) {
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$max = max $max, $sofar;
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}
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else {
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$inv_length = @left;
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$max = $sofar;
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}
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}
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