diff options
| -rwxr-xr-x | challenge-060/jo-37/perl/ch-2.pl | 43 |
1 files changed, 28 insertions, 15 deletions
diff --git a/challenge-060/jo-37/perl/ch-2.pl b/challenge-060/jo-37/perl/ch-2.pl index e9da2dcdbf..128128876a 100755 --- a/challenge-060/jo-37/perl/ch-2.pl +++ b/challenge-060/jo-37/perl/ch-2.pl @@ -1,21 +1,26 @@ #!/usr/bin/perl -# generate numbers of length $X that are smaller than $Y -# from the parts in @L. +# sub create_numbers generates numbers +# - of length $X +# - that are smaller than $Y +# - from the parts in @L. +# See below. # -# recursive "branch and cut" +# Performs recursive "branch and cut". +# Though data is numeric, processing is string based. use Test2::V0; +use Data::Dumper; # check_num expects: -# - number that has the desired length +# - number to be checked # - control hash. -# if the number fits, it is added to the result set. -# cut this branch otherwise +# If the number fits, it is added to the result set. +# Cut this branch otherwise. sub check_num { my $num = shift; my $ctl = shift; - if ($num lt $ctl->{limit}) { + if ($num < $ctl->{limit}) { return $ctl->{result}{$num} = 1 }; 0; @@ -45,12 +50,14 @@ sub gen_num { # construct current value from selected parts my $value = join '', @current; + + # test length of current value my $t = length($value) <=> $ctl->{length}; if ($t < 0) { # $value is too short - if ($value gt $ctl->{limit}) { - # cut if current prefix is already too large + if ($value ge $ctl->{limit}) { + # cut if $value is too large return; - } else { + } else { # $value is not too large but too short # recurse to next level gen_num $level + 1, $ctl; } @@ -82,18 +89,24 @@ sub create_numbers { } # main -my (@L, $X, $Y, @R); +my (@L, $X, $Y); @L = (0, 1, 2, 5); $X = 2; $Y = 21; -@R = create_numbers $X, $Y, @L; -is \@R, [10, 11, 12, 15, 20], 'example from challenge'; +is [create_numbers $X, $Y, @L], [10, 11, 12, 15, 20], + 'example from challenge'; @L = (0, 1, 100000002); $X = 9; $Y = 100000003; -@R = create_numbers $X, $Y, @L; -is \@R, [100000000, 100000001, 100000002], 'cut example'; +is [create_numbers $X, $Y, @L], [100000000, 100000001, 100000002], + 'cut example'; done_testing; + +# another example +@L = (0, 7, 65, 543, 4321); +$X = 5; +$Y = 70001; +print Dumper [create_numbers $X, $Y, @L]; |