# PWC 100
use strict;
use warnings;
use JSON::PP;
use Test::More;
use List::Util qw/reduce/;


while ( my $line = <DATA> ) {
    my ($json, $expected) = split /\s/, $line;
    my $aoa = decode_json($json);
    is( compute($aoa), $expected );
    compute($aoa);
}

sub compute {
    my @aoa = @{(shift)};

    my $bottom;
    while (@aoa) {
        $bottom = pop @aoa;
        my $i=0;

        reduce {                        # by overlapping pairs
            $aoa[-1][$i++] +=           # add to parent ...
              ($a < $b ? $a : $b);      # ... minimum neighbors
            $b                          # right to left nb
        } @$bottom;

    }

    return $bottom->[0];
}

done_testing;

__DATA__
[[1],[2,4],[6,4,9],[5,1,7,2]] 8
[[9],[1,6],[7,8,2],[5,8,2,3]] 19
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