diff options
| -rw-r--r-- | challenge-284/jeanluc2020/blog-1.txt | 1 | ||||
| -rw-r--r-- | challenge-284/jeanluc2020/blog-2.txt | 1 | ||||
| -rwxr-xr-x | challenge-284/jeanluc2020/perl/ch-1.pl | 59 | ||||
| -rwxr-xr-x | challenge-284/jeanluc2020/perl/ch-2.pl | 71 |
4 files changed, 132 insertions, 0 deletions
diff --git a/challenge-284/jeanluc2020/blog-1.txt b/challenge-284/jeanluc2020/blog-1.txt new file mode 100644 index 0000000000..7bf87cc718 --- /dev/null +++ b/challenge-284/jeanluc2020/blog-1.txt @@ -0,0 +1 @@ +http://gott-gehabt.de/800_wer_wir_sind/thomas/Homepage/Computer/perl/theweeklychallenge-284-1.html diff --git a/challenge-284/jeanluc2020/blog-2.txt b/challenge-284/jeanluc2020/blog-2.txt new file mode 100644 index 0000000000..8b200dfb54 --- /dev/null +++ b/challenge-284/jeanluc2020/blog-2.txt @@ -0,0 +1 @@ +http://gott-gehabt.de/800_wer_wir_sind/thomas/Homepage/Computer/perl/theweeklychallenge-284-2.html diff --git a/challenge-284/jeanluc2020/perl/ch-1.pl b/challenge-284/jeanluc2020/perl/ch-1.pl new file mode 100755 index 0000000000..4205b57f3e --- /dev/null +++ b/challenge-284/jeanluc2020/perl/ch-1.pl @@ -0,0 +1,59 @@ +#!/usr/bin/env perl +# https://theweeklychallenge.org/blog/perl-weekly-challenge-284/#TASK1 +# +# Task 1: Lucky Integer +# ===================== +# +# You are given an array of integers, @ints. +# +# Write a script to find the lucky integer if found otherwise return -1. If +# there are more than one then return the largest. +# +### A lucky integer is an integer that has a frequency in the array equal to +### its value. +# +## Example 1 +## +## Input: @ints = (2, 2, 3, 4) +## Output: 2 +# +## Example 2 +## +## Input: @ints = (1, 2, 2, 3, 3, 3) +## Output: 3 +# +## Example 3 +## +## Input: @ints = (1, 1, 1, 3) +## Output: -1 +# +############################################################ +## +## discussion +## +############################################################ +# +# Count the frequencies for all elements in the array. Then +# check the frequencies versus the value sorted in descending +# order and stop once we find a match. If there was no match, +# return -1. + +use strict; +use warnings; + +lucky_integer(2, 2, 3, 4); +lucky_integer(1, 2, 2, 3, 3, 3); +lucky_integer(1, 1, 1, 3); + +sub lucky_integer { + my @ints = @_; + print "Input: (" . join(", ", @ints) . ")\n"; + my $frequencies = {}; + foreach my $i (@ints) { + $frequencies->{$i}++; + } + foreach my $f (sort {$b<=>$a} keys %{$frequencies}) { + return print "Output: $f\n" if $frequencies->{$f} == $f; + } + print "Output: -1\n"; +} diff --git a/challenge-284/jeanluc2020/perl/ch-2.pl b/challenge-284/jeanluc2020/perl/ch-2.pl new file mode 100755 index 0000000000..b04a87b4aa --- /dev/null +++ b/challenge-284/jeanluc2020/perl/ch-2.pl @@ -0,0 +1,71 @@ +#!/usr/bin/env perl +# https://theweeklychallenge.org/blog/perl-weekly-challenge-284/#TASK2 +# +# Task 2: Relative Sort +# ===================== +# +# You are given two list of integers, @list1 and @list2. The elements in the +# @list2 are distinct and also in the @list1. +# +# Write a script to sort the elements in the @list1 such that the relative +# order of items in @list1 is same as in the @list2. Elements that is missing +# in @list2 should be placed at the end of @list1 in ascending order. +# +## Example 1 +## +## Input: @list1 = (2, 3, 9, 3, 1, 4, 6, 7, 2, 8, 5) +## @list2 = (2, 1, 4, 3, 5, 6) +## Ouput: (2, 2, 1, 4, 3, 3, 5, 6, 7, 8, 9) +# +## Example 2 +## +## Input: @list1 = (3, 3, 4, 6, 2, 4, 2, 1, 3) +## @list2 = (1, 3, 2) +## Ouput: (1, 3, 3, 3, 2, 2, 4, 4, 6) +# +## Example 3 +## +## Input: @list1 = (3, 0, 5, 0, 2, 1, 4, 1, 1) +## @list2 = (1, 0, 3, 2) +## Ouput: (1, 1, 1, 0, 0, 3, 2, 4, 5) +# +############################################################ +## +## discussion +## +############################################################ +# +# First, we turn the second list into a hash with the integers +# as keys and their position inside the array as the values. +# Then we run a clever compare function: +# - if there is an entry for both numbers to be compared, we just +# compare their position in the original list2. +# - if only one of the two numbers has an entry in the hash, sort +# this number first +# - if both numbers are missing in list2, then sort by their value + +use strict; +use warnings; + +relative_sort( [2, 3, 9, 3, 1, 4, 6, 7, 2, 8, 5], [2, 1, 4, 3, 5, 6] ); +relative_sort( [3, 3, 4, 6, 2, 4, 2, 1, 3], [1, 3, 2] ); +relative_sort( [3, 0, 5, 0, 2, 1, 4, 1, 1], [1, 0, 3, 2] ); + +sub relative_sort { + my ($list1, $list2) = @_; + print "Input: (" . join(", ", @$list1) . "),\n (" . join(", ", @$list2) . ")\n"; + my $int_to_index = {}; + my $i = 0; + foreach my $elem (@$list2) { + $int_to_index->{$elem} = $i; + $i++; + } + my @sorted = sort { + ( defined($int_to_index->{$a}) && defined($int_to_index->{$b}) && + $int_to_index->{$a} <=> $int_to_index->{$b} ) || + ( defined($int_to_index->{$a}) && -1 ) || + ( defined($int_to_index->{$b}) && 1 ) || + $a <=> $b + } @$list1; + print "Output: (" . join(", ", @sorted) . ")\n"; +} |