use integer;
my $start = time;
while(<DATA>){
  if(/#----END----#/){ 
    my $duration = time - $start;
    die "Execution time: $duration s\n";
  }
  @A = split //,; &R; 
}
sub R { 
    for $i ( 0 .. 80 ) { 
        next if $A[$i];
        my %t = map {
          $_/9==$i/9||$_%9==$i%9||$_/27==$i/27&&$_%9/3==$i%9/3?$A[$_]:0=>1
        } 0 .. 80; 
        R($A[$i]=$_) for grep{!$t{$_}} 1 .. 9;
        return $A[$i] = 0;
    }   
    $sum=0; for(@A){$sum+=$_} print" $sum\n";
    warn @A;          # Execution time = 717 s
#    die @A;          # Execution time 31 + 31 + 14 + 1 + 5 = 82 s
}
__DATA__
120400300300010050006000100700090000040603000003002000500080700007000005000000098
000000039000001005003050800008090006070002000100400000009080050020000600400700000
120300004350000100004000000005400200600070000000008090003100500000009070000060008
003000000400080036008000100040060073000900000000002005004070068600000000700600500
800000000003600000070090200050007000000045700000100030001000068008500010090000400
#----END----# 
128465379374219856956837142765198423249673581813542967592386714487921635631754298
751846239892371465643259871238197546974562318165438927319684752527913684486725193
126395784359847162874621953985416237631972845247538691763184529418259376592763418
123456789457189236968327154249561873576938412831742695314275968695814327782693541
812753649943682175675491283154237896369845721287169534521974368438526917796318452