Add solution for challenge 194

Signed-off-by: Thomas Köhler <jean-luc@picard.franken.de>

2 files changed, 86 insertions, 0 deletions

diff --git a/challenge-194/jeanluc2020/perl/ch-1.pl b/challenge-194/jeanluc2020/perl/ch-1.pl
new file mode 100755
index 0000000000..5e2ef47200
--- /dev/null
+++ b/challenge-194/jeanluc2020/perl/ch-1.pl
@@ -0,0 +1,43 @@
+#!/usr/bin/perl
+# ch-1.pl
+#
+# You are given time in the format hh:mm with one missing digit.
+# Write a script to find the highest digit between 0-9 that makes it valid time.
+
+use warnings;
+use strict;
+use Data::Dumper;
+
+my @times = (
+    '?5:00',
+    '?3:00',
+    '1?:00',
+    '2?:00',
+    '12:?5',
+    '12:5?'
+);
+
+foreach my $time (@times) {
+    my ($output, $newtime) = calculate($time);
+    print "$time -> $output ($newtime)\n";
+}
+
+sub calculate {
+    my $time = shift;
+    if ($time =~ m/^\?([0-3]:\d\d)$/) { # 20:XX - 23:XX
+        return (2, "2$1");
+    } elsif ($time =~ m/^\?(\d:\d\d)$/) { # 14:XX - 19:XX
+        return (1, "1$1");
+    } elsif ($time =~ m/^2\?(:\d\d)$/) { # 23:XX
+        return (3, "23$1");
+    } elsif ($time =~ m/^([01])\?(:\d\d)$/) { # 09:XX or 19:XX
+        return (9, "${1}9$2");
+    } elsif ($time =~ m/^(\d\d:)\?(\d)$/) { # XX:5X
+        return (5, "${1}5$2");
+    } elsif ($time =~ m/^(\d\d:\d)\?$/) { # XX:X9
+        return (9, "${1}9");
+    } else {
+        die "Invalid time $time!\n";
+    }
+}
+
diff --git a/challenge-194/jeanluc2020/perl/ch-2.pl b/challenge-194/jeanluc2020/perl/ch-2.pl
new file mode 100755
index 0000000000..ce28ff9a45
--- /dev/null
+++ b/challenge-194/jeanluc2020/perl/ch-2.pl
@@ -0,0 +1,43 @@
+#!/usr/bin/perl
+# ch-2.pl
+#
+# You are given a string made of alphabetic characters only, a-z.
+# Write a script to determine whether removing only one character can make the frequency of the remaining characters the same.
+
+use warnings;
+use strict;
+
+my @strings = (
+    "abbc",
+    "xyzyyxz",
+    "xzxz"
+);
+
+foreach my $string (@strings) {
+    my $output = calculate($string);
+    print "$string -> $output\n";
+}
+
+sub calculate {
+    my $string = shift;
+    my @parts = split //, $string;
+    my $map = {};
+    my $reverse_map = {};
+    # map will contain the frequency of each character
+    map { $map->{$_}++ } @parts;
+    # let's count all frequencies
+    foreach my $key (keys %$map) {
+        $reverse_map->{ $map->{$key} }//=0;
+        $reverse_map->{ $map->{$key} }++;
+    }
+    # if we have more or less than 2 frequencies then
+    # removing one character won't end up in the same
+    # frequency for all characters
+    if(scalar(keys(%$reverse_map)) != 2) {
+        return 0;
+    }
+    # let's sort the different frequencies
+    my ($first, $second) = sort {$a <=> $b} keys %$reverse_map;
+    return 1 if $first+1 == $second && $reverse_map->{$second} == 1;
+    return 0;
+}