diff options
| author | James Smith <js5@sanger.ac.uk> | 2022-04-30 00:24:44 +0100 |
|---|---|---|
| committer | GitHub <noreply@github.com> | 2022-04-30 00:24:44 +0100 |
| commit | ed9f1c31c68fa6bc8754f730e56e60ebf1c59e04 (patch) | |
| tree | 277dacc2bad9a5c3ea05e53df924c77602af3c71 /challenge-162 | |
| parent | 16e89bebcfa7e9ff3c620eaaa9a2dfa5515738cc (diff) | |
| download | perlweeklychallenge-club-ed9f1c31c68fa6bc8754f730e56e60ebf1c59e04.tar.gz perlweeklychallenge-club-ed9f1c31c68fa6bc8754f730e56e60ebf1c59e04.tar.bz2 perlweeklychallenge-club-ed9f1c31c68fa6bc8754f730e56e60ebf1c59e04.zip | |
Update README.md
Diffstat (limited to 'challenge-162')
| -rw-r--r-- | challenge-162/james-smith/README.md | 15 |
1 files changed, 10 insertions, 5 deletions
diff --git a/challenge-162/james-smith/README.md b/challenge-162/james-smith/README.md index 106cb78373..248d432347 100644 --- a/challenge-162/james-smith/README.md +++ b/challenge-162/james-smith/README.md @@ -24,9 +24,15 @@ Rather than computing the checksum - as we have ISBN numbers with the checksum w ```perl sub validate_isbn13 { - my( $s, @p ) = ( 0, grep {/\d/} split //, $_[0] ); - $s -= shift(@p) + 3*shift @p for 0..5; - $p[0] == $s%10; + my @p = ( my $s = 0, grep {/\d/} split //, $_[0] ); + $s += 3*shift(@p) + shift @p while @p; + !($s%10); +} + +sub checksum_isbn13 { + my($s,@p) = ( 0, @{[grep {/\d/} split //, $_[0]]}[0..11] ); ## Remove checksum if present.. + $s -= shift(@p) + 3*shift @p while @p; + $s%10; } ``` @@ -48,7 +54,7 @@ sub _crypt { ($_ eq 'j' && ($_='i')), exists $l{$_} || ($l{$_}=[int $p/5,($p++)%5]) for grep { /[a-z]/ } split(//,$key),'a'..'i','j'..'z'; $r[$l{$_}[0]][$l{$_}[1]]=$_ for keys %l; - my @seq = grep {/[a-z]/} split //, shift =~ s{j}{j}gr; ## Prep sequence + my @seq = grep {/[a-z]/} split //, shift =~ s{j}{i}gr; ## Prep sequence while(my($m,$n)=splice @seq,0,2) { ## Loop through letter pairs unshift(@seq,$n), $n='x' if $n && $n eq $m and $n ne 'x'; ## Deal with case when both letters the same @@ -61,4 +67,3 @@ sub _crypt { $out; } ``` - |