use strict;
use warnings;
use List::Util qw( sum min );

my @dist = <DATA>;
$_ = [ split /\s+/ ] and shift @$_ for @dist;
my $glength = 0.5 * sum map { sum @$_ } @dist;

sub path_recursive {
  my( $bound, $len, $path, $end, $tbv, $dist ) = @_;

  if( !@$tbv ) {
    $len += $dist->[ $path->[-1] ]->[$end];
    if( $len < $glength ) {
      $glength = $len;
      print "$len: @$path $end ",scalar(localtime),"\n";
    }
    return;
  }

  my $last = $dist->[ $path->[-1] ];
  my @sorted = sort { $last->[$a] <=> $last->[$b] } @$tbv;

  for (1..min($bound,@sorted)){
    my $next = shift @sorted;
    path_recursive( $bound, $len + $last->[$next], [ @$path, $next ], 
+$end, [ @sorted ], $dist );
    push @sorted, $next;
  }
}

path_recursive shift(), 0, [ 1 ], 24, [ 2..23 ], \@dist;

__DATA__
     0   1     2     3     4     5     6     7     8     9    10    11
+    12    13    14    15    16    17    18    19    20    21    22   
+ 23    24
     1     0  3812 13902  8619 15811  5015  5230  9615 10624 13346  75
+75  6170  6812  9487 18135  8030  5409 17959 12822 17136  3267 12882 
+11223 11078
     2  3812     0 11527 12431 15446  8057  4519  8761 14398 12569  37
+64  6668 10603 11117 14805  5154  8276 18175  9367 14840  7056  9698 
+13603  7266
     3 13902 11527     0 13638 10220 18405  8675  4611 12993 11970  87
+98  8226 15087 16591  6859  6381 11223  7602  3236  3457 14535  8830 
+14748  6655
     4  8619 12431 13638     0  9965  5555 11256 11549  2157 10917 161
+94  9609  1926  7111 12565 14906  5737  9378 16868 11899  5402 15921 
+ 5765 19675
     5 15811 15446 10220  9965     0 11122 18683 14599  7873  2940 131
+19 17793 11057  6374  3517 14973 15565  3627 10307  7077 14478  6475 
+ 5155 10235
     6  5015  8057 18405  5555 11122     0 10109 13856  6744  9617 113
+48 10270  3811  4858 14594 12975  7186 13212 17301 17106  3881 12658 
+ 6210 14138
     7  5230  4519  8675 11256 18683 10109     0  4584 13284 16923  60
+18  2299 10267 14709 15205  3741  5549 15863  8377 11981  6865 12543 
+16177  8600
     8  9615  8761  4611 11549 14599 13856  4584     0 12503 16548  82
+40  3619 11888 18524 11444  4627  6948 11282  6102  7523  9992 12321 
+16782  8550
     9 10624 14398 12993  2157  7873  6744 13284 12503     0  9231 180
+70 11405  3813  6447 10427 16699  7735  7340 15982 10421  7492 14151 
+ 4374 18092
    10 13346 12569 11970 10917  2940  9617 16923 16548  9231     0 110
+52 19220 11199  4874  5269 14093 16358  6543 10709  9458 13488  5008 
+ 5170  9146
    11  7575  3764  8798 16194 13119 11348  6018  8240 18070 11052    
+ 0  8220 14354 12490 11186  3614 11306 14452  5954 11533 10801  6649 
+14987  3508
    12  6170  6668  8226  9609 17793 10270  2299  3619 11405 19220  82
+20     0  9124 15115 15059  5330  3975 14165  9100 10994  6469 14453 
+15268 10326
    13  6812 10603 15087  1926 11057  3811 10267 11888  3813 11199 143
+54  9124     0  6645 14126 13999  5168 11153 17968 13808  3728 15782 
+ 6168 17749
    14  9487 11117 16591  7111  6374  4858 14709 18524  6447  4874 124
+90 15115  6645     0  9754 15942 11588  9288 15400 13331  8652  9157 
+ 2621 12782
    15 18135 14805  6859 12565  3517 14594 15205 11444 10427  5269 111
+86 15059 14126  9754     0 11725 16484  3379  6883  4250 17835  5311 
+ 8643  7729
    16  8030  5154  6381 14906 14973 12975  3741  4627 16699 14093  36
+14  5330 13999 15942 11725     0  9173 13841  4874  9780 10451  9122 
+18555  5003
    17  5409  8276 11223  5737 15565  7186  5549  6948  7735 16358 113
+06  3975  5168 11588 16484  9173     0 13413 12955 12642  3450 17931 
+11293 14142
    18 17959 18175  7602  9378  3627 13212 15863 11282  7340  6543 144
+52 14165 11153  9288  3379 13841 13413     0  9181  4145 14775  8581 
+ 7147 10945
    19 12822  9367  3236 16868 10307 17301  8377  6102 15982 10709  59
+54  9100 17968 15400  6883  4874 12955  9181     0  5593 15242  6278 
+15447  3419
    20 17136 14840  3457 11899  7077 17106 11981  7523 10421  9458 115
+33 10994 13808 13331  4250  9780 12642  4145  5593     0 15914  8478 
+11291  8453
    21  3267  7056 14535  5402 14478  3881  6865  9992  7492 13488 108
+01  6469  3728  8652 17835 10451  3450 14775 15242 15914     0 15624 
+ 9326 14308
    22 12882  9698  8830 15921  6475 12658 12543 12321 14151  5008  66
+49 14453 15782  9157  5311  9122 17931  8581  6278  8478 15624     0 
+10157  4139
    23 11223 13603 14748  5765  5155  6210 16177 16782  4374  5170 149
+87 15268  6168  2621  8643 18555 11293  7147 15447 11291  9326 10157 
+    0 14265
    24 11078  7266  6655 19675 10235 14138  8600  8550 18092  9146  35
+08 10326 17749 12782  7729  5003 14142 10945  3419  8453 14308  4139 
+14265     0
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