- Added solutions by Ulrich Rieke.

7 files changed, 248 insertions, 0 deletions

diff --git a/challenge-156/ulrich-rieke/cpp/ch-1.cpp b/challenge-156/ulrich-rieke/cpp/ch-1.cpp
new file mode 100644
index 0000000000..abcbd0512b
--- /dev/null
+++ b/challenge-156/ulrich-rieke/cpp/ch-1.cpp
@@ -0,0 +1,45 @@
+#include <vector>
+#include <iostream>
+#include <algorithm>
+#include <cmath>
+
+bool isPrime( int n ) {
+  if ( n == 1 )
+      return false ;
+  if ( n == 2 )
+      return true ;
+  int root = static_cast<int>( floor( sqrt( static_cast<double>( n ) ))) ;
+  for ( int i = 2 ; i < root + 1 ; i++ )
+      if ( n % i == 0 )
+        return false ;
+  return true ;
+}
+
+std::vector<int> toBinary( int n ) {
+  std::vector<int> binaryDigits ;
+  while ( n != 0 ) {
+      binaryDigits.push_back( n % 2 ) ;
+      n /= 2 ;
+  }
+  return binaryDigits ;
+}
+
+bool isPernicious( int n ) {
+  std::vector<int> binaryDigits { toBinary( n ) } ;
+  return isPrime( std::count( binaryDigits.begin( ) , binaryDigits.end( ) ,
+        1 )) ;
+}
+
+int main( ) {
+  std::vector<int> perniciousNumbers ;
+  int current = 0 ;
+  while ( perniciousNumbers.size( ) != 10 ) {
+      current++ ;
+      if ( isPernicious( current ) )
+    perniciousNumbers.push_back( current ) ;
+  }
+  for ( int i : perniciousNumbers )
+      std::cout << i << ' ' ;
+  std::cout << std::endl ;
+  return 0 ;
+}
diff --git a/challenge-156/ulrich-rieke/haskell/ch-1.hs b/challenge-156/ulrich-rieke/haskell/ch-1.hs
new file mode 100644
index 0000000000..bf2ea90b69
--- /dev/null
+++ b/challenge-156/ulrich-rieke/haskell/ch-1.hs
@@ -0,0 +1,37 @@
+module Challenge156
+  where
+import Control.Monad.State.Lazy
+import Data.Maybe ( fromJust )
+import Data.Char ( intToDigit )
+
+findBases :: Int -> State ( Int , String ) String
+findBases theBase = do
+  (number , basenumberstring) <- get
+  if number == 0
+      then return (reverse basenumberstring)
+  else do
+      put ( div number theBase , basenumberstring ++
+            [ fromJust $ lookup ( mod number theBase ) positions ] )
+      findBases theBase
+
+convertToBase :: Int -> Int -> String
+convertToBase number base = evalState (findBases base ) ( number , [] )
+
+isPrime :: Integer -> Bool
+isPrime n
+  |n == 1 = False
+  |n == 2 = True
+  |otherwise = null $ filter (\i -> mod n i == 0 ) [2 .. toInteger root]
+  where
+      root :: Int
+      root = round $ sqrt $ fromIntegral n
+
+positions :: [(Int , Char) ]
+positions = zip [0..35] ( (map intToDigit [0..9]) ++ ['A'..'Z'] )
+
+isPernicious :: Int -> Bool
+isPernicious n = isPrime $ toInteger $ length $ filter ( == '1' )
+$ convertToBase n 2
+
+solution :: [Int]
+solution = take 10 $ filter isPernicious [1 , 2 ..]
diff --git a/challenge-156/ulrich-rieke/haskell/ch-2.hs b/challenge-156/ulrich-rieke/haskell/ch-2.hs
new file mode 100644
index 0000000000..c24db6a493
--- /dev/null
+++ b/challenge-156/ulrich-rieke/haskell/ch-2.hs
@@ -0,0 +1,16 @@
+module Challenge156_2
+  where
+import Data.List ( any , subsequences )
+
+isWeird :: Int -> Bool
+isWeird n = (sum properDivisors > n) && ( not $ any ( == n ) $ map sum $
+filter (\li -> (length li > 1) && (length li < len) ) $ subsequences
+properDivisors )
+where
+  properDivisors :: [Int]
+  properDivisors = [d | d <- [1 .. div n 2 + 1] , mod n d == 0]
+  len            :: Int
+  len            = length properDivisors
+
+solution :: Int -> Int
+solution n = if isWeird n then 1 else 0
diff --git a/challenge-156/ulrich-rieke/perl/ch-1.pl b/challenge-156/ulrich-rieke/perl/ch-1.pl
new file mode 100644
index 0000000000..0d9e665940
--- /dev/null
+++ b/challenge-156/ulrich-rieke/perl/ch-1.pl
@@ -0,0 +1,51 @@
+#!/usr/bin/perl ;
+use strict ;
+use warnings ;
+use feature 'say' ;
+use POSIX ;
+
+sub isPrime {
+  my $number = shift ;
+  if ( $number == 1 ) {
+      return 0 ;
+  }
+  elsif ( $number == 2 ) {
+      return 1 ;
+  }
+  else {
+      my $root = ceil( sqrt( $number ) ) ;
+      for my $i ( 2 .. $root ) {
+        if ( $number % $i == 0 ) {
+            return 0 ;
+        }
+      }
+      return 1 ;
+  }
+}
+
+sub toBinary {
+  my $num = shift ;
+  my @nums ;
+  while ( $num != 0 ) {
+      my $remainder = $num % 2 ;
+      push @nums, $remainder ;
+      $num = floor ( $num / 2 ) ;
+  }
+  return reverse @nums ;
+}
+
+sub isPernicious {
+  my $number = shift ;
+  my @binary = toBinary( $number ) ;
+  return isPrime( scalar( grep { $_ == 1 } @binary ) ) ;
+}
+
+my @perniciousNumbers ;
+my $current = 0 ;
+while ( scalar( @perniciousNumbers ) != 10 ) {
+  $current++ ;
+  if ( isPernicious( $current ) ) {
+      push @perniciousNumbers, $current ;
+  }
+}
+say join( ',' , @perniciousNumbers ) ;
diff --git a/challenge-156/ulrich-rieke/perl/ch-2.pl b/challenge-156/ulrich-rieke/perl/ch-2.pl
new file mode 100644
index 0000000000..db655eac8a
--- /dev/null
+++ b/challenge-156/ulrich-rieke/perl/ch-2.pl
@@ -0,0 +1,40 @@
+#!/usr/bin/perl ;
+use strict ;
+use warnings ;
+use feature 'say' ;
+use List::Util qw ( sum ) ;
+use Algorithm::Combinatorics qw( combinations ) ;
+
+sub findProperDivisors {
+  my $number = shift ;
+  my @divisors = ( 1 ) ;
+  for my $i ( 2 .. int( $number / 2 ) + 1 ) {
+      if ( $number % $i == 0 ) {
+    push @divisors , $i ;
+      }
+  }
+  return @divisors ;
+}
+
+my $n = $ARGV[0] ;
+my $isWeird = 1 ;
+my @divisors = findProperDivisors( $n ) ;
+if ( sum( @divisors ) <= $n ) {
+  $isWeird = 0 ;
+}
+else {
+  for my $i ( 2 .. scalar( @divisors ) - 1 ) {
+      my $iter = combinations( \@divisors , $i ) ;
+      while ( my $c = $iter->next ) {
+    if ( sum( @$c ) == $n ) {
+        $isWeird = 0 ;
+    }
+      }
+  }
+}
+if ( $isWeird == 1 ) {
+  say 1 ;
+}
+else {
+  say 0 ;
+}
diff --git a/challenge-156/ulrich-rieke/raku/ch-1.raku b/challenge-156/ulrich-rieke/raku/ch-1.raku
new file mode 100644
index 0000000000..eb5005b97a
--- /dev/null
+++ b/challenge-156/ulrich-rieke/raku/ch-1.raku
@@ -0,0 +1,22 @@
+use v6 ;
+
+sub isPernicious( Int $n is copy  --> Bool ) {
+  my $binaryString = $n.base( 2 ) ;
+  my $ones = 0 ;
+  for (0 .. $binaryString.chars - 1) -> $i {
+      if ( $binaryString.substr( $i , 1 ) eq "1" ) {
+    $ones++ ;
+      }
+  }
+  return $ones.is-prime ;
+}
+
+my @perniciousNumbers ;
+my $current = 0;
+while ( @perniciousNumbers.elems != 10 ) {
+  $current++ ;
+  if (isPernicious( $current ) ) {
+      @perniciousNumbers.push( $current ) ;
+  }
+}
+say @perniciousNumbers.join( ',' ) ;
diff --git a/challenge-156/ulrich-rieke/raku/ch-2.raku b/challenge-156/ulrich-rieke/raku/ch-2.raku
new file mode 100644
index 0000000000..438e076bc6
--- /dev/null
+++ b/challenge-156/ulrich-rieke/raku/ch-2.raku
@@ -0,0 +1,37 @@
+use v6 ;
+
+sub findDivisors( Int $n is copy ) {
+  my @divisors = ( 1 ) ;
+  my $current = 2 ;
+  while ( $current < $n div 2 + 1 ) {
+      if ( $n %% $current ) {
+    @divisors.push( $current ) ;
+      }
+      $current++ ;
+  }
+  return @divisors ;
+}
+
+sub MAIN( $n is copy ) {
+  my @divisors = findDivisors( $n ) ;
+  my Bool $isWeird = True ;
+  if ( ([+] @divisors) <= $n ) {
+      $isWeird = False ;
+  }
+  else {
+      for ( 2 .. @divisors.elems - 1 ) -> $i {
+    my @sums = @divisors.combinations( $i ).map( {.sum} ) ;
+    for (0 .. @sums.elems - 1 ) -> $j {
+        if ( @sums[ $j ] == $n ) {
+          $isWeird = False ;
+        }
+    }
+      }
+  }
+  if ( $isWeird ) {
+      say 1 ;
+  }
+  else {
+      say 0 ;
+  }
+}