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| -rwxr-xr-x | challenge-147/jo-37/perl/ch-1.pl | 70 |
1 files changed, 70 insertions, 0 deletions
diff --git a/challenge-147/jo-37/perl/ch-1.pl b/challenge-147/jo-37/perl/ch-1.pl new file mode 100755 index 0000000000..bef3fd8a26 --- /dev/null +++ b/challenge-147/jo-37/perl/ch-1.pl @@ -0,0 +1,70 @@ +#!/usr/bin/perl -s + +use v5.24; +use Test2::V0; +use warnings FATAL => 'all'; +use Math::Prime::Util qw(fromdigits todigits is_prime); +use Data::Dump qw(dd pp); +use experimental 'signatures'; + +our ($tests, $examples, $base); +$base ||= 10; + +run_tests() if $tests || $examples; # does not return + +die <<EOS unless @ARGV; +usage: $0 [-examples] [-tests] [-base=B] [N] + +-examples + run the examples from the challenge + +-tests + run some tests + +-base=B + use base B. Default: 10 + +N + check if N is a left-truncatable prime in base B + +EOS + + +### Input and Output + +say 0 + !!is_truncatable_prime(shift, $base); + + +### Implementation + +sub is_truncatable_prime ($p, $b) { + my @p = todigits($p, $b); + while (@p) { + $p = fromdigits([@p], $b); + return unless is_prime($p); + shift @p; + } + 1; +} + + +### Examples and tests + +sub run_tests { + SKIP: { + skip "examples" unless $examples; + + ok is_truncatable_prime(9137, 10), 'example'; + } + + SKIP: { + skip "tests" unless $tests; + + ok !is_truncatable_prime(15, 10), '15'; + ok is_truncatable_prime(17, 10), '17'; + ok !is_truncatable_prime(19, 10), '19'; + } + + done_testing; + exit; +} |
