Merge pull request #7131 from Firedrake/rogerbw-challenge-192

Solutions for challenge #192

18 files changed, 790 insertions, 0 deletions

diff --git a/challenge-192/roger-bell-west/javascript/ch-1.js b/challenge-192/roger-bell-west/javascript/ch-1.js
new file mode 100755
index 0000000000..c81f2c7f45
--- /dev/null
+++ b/challenge-192/roger-bell-west/javascript/ch-1.js
@@ -0,0 +1,34 @@
+#! /usr/bin/node
+
+"use strict"
+
+function binaryflip(n) {
+    let m = n;
+    let r = 0;
+    while (m > 0) {
+        m >>= 1;
+        r += 1;
+    }
+    return (1 << r) - 1 - n;
+}
+
+if (binaryflip(5) == 2) {
+    process.stdout.write("Pass");
+} else {
+    process.stdout.write("FAIL");
+}
+process.stdout.write(" ");
+
+if (binaryflip(4) == 3) {
+    process.stdout.write("Pass");
+} else {
+    process.stdout.write("FAIL");
+}
+process.stdout.write(" ");
+
+if (binaryflip(6) == 1) {
+    process.stdout.write("Pass");
+} else {
+    process.stdout.write("FAIL");
+}
+process.stdout.write("\n");
diff --git a/challenge-192/roger-bell-west/javascript/ch-2.js b/challenge-192/roger-bell-west/javascript/ch-2.js
new file mode 100755
index 0000000000..66191166ec
--- /dev/null
+++ b/challenge-192/roger-bell-west/javascript/ch-2.js
@@ -0,0 +1,58 @@
+#! /usr/bin/node
+
+"use strict"
+
+function equaldistribution(list) {
+    let s = list.reduce((x, y) => x + y, 0);
+    if (s % list.length != 0) {
+        return -1;
+    }
+    let m = s / list.length;
+    let out = 0;
+    let w = list;
+    while (true) {
+        for (let i = 0; i < w.length-1; i++) {
+            if (w[i] > m) {
+                let v = w[i] - m;
+                w[i+1] += v;
+                out += v;
+                w[i] = m;
+            } else if (w[i] < m) {
+                let v = Math.min(m - w[i], w[i+1]);
+                w[i+1] -= v;
+                out += v;
+                w[i] += v;
+            }
+        }
+        let done = true;
+        for (let v of w) {
+            if (v != m) {
+                done = false;
+                break;
+            }
+        }
+        if (done) {
+            break;
+        }
+    }
+    return out;
+}
+
+if (equaldistribution([1, 0, 5]) == 4) {
+    process.stdout.write("Pass");
+} else {
+    process.stdout.write("FAIL");
+}
+process.stdout.write(" ");
+if (equaldistribution([0, 2, 0]) == -1) {
+    process.stdout.write("Pass");
+} else {
+    process.stdout.write("FAIL");
+}
+process.stdout.write(" ");
+if (equaldistribution([0, 3, 0]) == 2) {
+    process.stdout.write("Pass");
+} else {
+    process.stdout.write("FAIL");
+}
+process.stdout.write("\n");
diff --git a/challenge-192/roger-bell-west/kotlin/ch-1.kt b/challenge-192/roger-bell-west/kotlin/ch-1.kt
new file mode 100644
index 0000000000..c8eeb9470a
--- /dev/null
+++ b/challenge-192/roger-bell-west/kotlin/ch-1.kt
@@ -0,0 +1,30 @@
+fun binaryflip(n: Int): Int {
+    var m = n
+    var r = 0
+    while (m > 0) {
+        m = m shr 1
+        r += 1
+    }
+    return (1 shl r) - 1 - n
+}
+
+fun main() {
+    if (binaryflip(5) == 2) {
+        print("Pass")
+    } else {
+        print("FAIL")
+    }
+    print(" ")
+    if (binaryflip(4) == 3) {
+        print("Pass")
+    } else {
+        print("FAIL")
+    }
+    print(" ")
+    if (binaryflip(6) == 1) {
+        print("Pass")
+    } else {
+        print("FAIL")
+    }
+    println("")
+}
diff --git a/challenge-192/roger-bell-west/kotlin/ch-2.kt b/challenge-192/roger-bell-west/kotlin/ch-2.kt
new file mode 100644
index 0000000000..e8d43ae9e6
--- /dev/null
+++ b/challenge-192/roger-bell-west/kotlin/ch-2.kt
@@ -0,0 +1,58 @@
+import kotlin.math.*
+
+fun equaldistribution(list: List<Int>): Int {
+    val s = list.sum()
+    if (s % list.size != 0) {
+        return -1
+    }
+    val m = s / list.size
+    var o: Int = 0
+    var w = ArrayList(list)
+    while (true) {
+        for (i in 0..w.size-2) {
+            if (w[i] > m) {
+                val v = w[i] - m
+                w[i+1] += v
+                o += v
+                w[i] = m
+            } else if (w[i] < m) {
+                val v = minOf(m - w[i], w[i+1])
+                w[i+1] -= v
+                o += v
+                w[i] += v
+            }
+        }
+        var done = true
+        for (v in w) {
+            if (v != m) {
+                done = false
+                break
+            }
+        }
+        if (done) {
+            break
+        }
+    }
+    return o
+}
+
+fun main() {
+    if (equaldistribution(listOf(1, 0, 5)) == 4) {
+        print("Pass")
+    } else {
+        print("FAIL")
+    }
+    print(" ")   
+    if (equaldistribution(listOf(0, 2, 0)) == -1) {
+        print("Pass")
+    } else {
+        print("FAIL")
+    }
+    print(" ")   
+    if (equaldistribution(listOf(0, 3, 0)) == 2) {
+        print("Pass")
+    } else {
+        print("FAIL")
+    }
+    println("")
+}
diff --git a/challenge-192/roger-bell-west/lua/ch-1.lua b/challenge-192/roger-bell-west/lua/ch-1.lua
new file mode 100755
index 0000000000..b3523f34ae
--- /dev/null
+++ b/challenge-192/roger-bell-west/lua/ch-1.lua
@@ -0,0 +1,32 @@
+#! /usr/bin/lua
+
+function binaryflip(n)
+   local m = n
+   local r = 0
+   while m > 0 do
+      m = m >> 1
+      r = r + 1
+   end
+   return (1 << r) - 1 - n
+end
+
+if binaryflip(5) == 2 then
+   io.write("Pass")
+else
+   io.write("FAIL")
+end
+io.write(" ")
+
+if binaryflip(4) == 3 then
+   io.write("Pass")
+else
+   io.write("FAIL")
+end
+io.write(" ")
+
+if binaryflip(6) == 1 then
+   io.write("Pass")
+else
+   io.write("FAIL")
+end
+print("")
diff --git a/challenge-192/roger-bell-west/lua/ch-2.lua b/challenge-192/roger-bell-west/lua/ch-2.lua
new file mode 100755
index 0000000000..90a1afe43c
--- /dev/null
+++ b/challenge-192/roger-bell-west/lua/ch-2.lua
@@ -0,0 +1,61 @@
+#! /usr/bin/lua
+
+function equaldistribution(list)
+   local s = 0
+   for i,v in ipairs(list) do
+      s = s + v
+   end
+   if s % #list ~= 0 then
+      return -1
+   end
+   local m = s / #list
+   local out = 0
+   local w = list
+   while true do
+      for i = 1,#w-1 do
+         if w[i] > m then
+            v = w[i] - m
+            w[i+1] = w[i+1] + v
+            out = out + v
+            w[i] = m
+         elseif w[i] < m then
+            v = math.min(m - w[i], w[i+1])
+            w[i+1] = w[i+1] - v
+            out = out + v
+            w[i] = w[i] + v
+         end
+      end
+      local done = true
+      for i,v in ipairs(w) do
+         if v ~= m then
+            done = false
+            break
+         end
+      end
+      if done then
+         break
+      end
+   end
+   return out
+end
+
+if equaldistribution({1, 0, 5}) == 4 then
+   io.write("Pass")
+else
+   io.write("FAIL")
+end
+io.write(" ")
+
+if equaldistribution({0, 2, 0}) == -1 then
+   io.write("Pass")
+else
+   io.write("FAIL")
+end
+io.write(" ")
+
+if equaldistribution({0, 3, 0}) == 2 then
+   io.write("Pass")
+else
+   io.write("FAIL")
+end
+print("")
diff --git a/challenge-192/roger-bell-west/perl/ch-1.pl b/challenge-192/roger-bell-west/perl/ch-1.pl
new file mode 100755
index 0000000000..9dd8abf9a4
--- /dev/null
+++ b/challenge-192/roger-bell-west/perl/ch-1.pl
@@ -0,0 +1,21 @@
+#! /usr/bin/perl
+
+use strict;
+use warnings;
+use experimental 'signatures';
+
+use Test::More tests => 3;
+
+is(binaryflip(5), 2, 'example 1');
+is(binaryflip(4), 3, 'example 2');
+is(binaryflip(6), 1, 'example 3');
+
+sub binaryflip($n) {
+    my $m = $n;
+    my $r = 0;
+    while ($m > 0) {
+        $m >>= 1;
+        $r++;
+    }
+    return (1 << $r) - 1 - $n;
+}
diff --git a/challenge-192/roger-bell-west/perl/ch-2.pl b/challenge-192/roger-bell-west/perl/ch-2.pl
new file mode 100755
index 0000000000..20c9dc5081
--- /dev/null
+++ b/challenge-192/roger-bell-west/perl/ch-2.pl
@@ -0,0 +1,48 @@
+#! /usr/bin/perl
+
+use strict;
+use warnings;
+use experimental 'signatures';
+
+use Test::More tests => 3;
+use List::Util qw(sum min);
+
+is(equaldistribution([1, 0, 5]), 4, 'example 1');
+is(equaldistribution([0, 2, 0]), -1, 'example 2');
+is(equaldistribution([0, 3, 0]), 2, 'example 3');
+
+sub equaldistribution($list) {
+  my $s = sum(@{$list});
+  if ($s % (scalar @{$list}) != 0) {
+    return -1;
+  }
+  my $m = $s / scalar @{$list};
+  my $out = 0;
+  my @w = @{$list};
+  while (1) {
+    foreach my $i (0..$#w-1) {
+      if ($w[$i] > $m) {
+        my $v = $w[$i] - $m;
+        $w[$i+1] += $v;
+        $out += $v;
+        $w[$i] = $m;
+      } elsif ($w[$i] < $m) {
+        my $v = min($m - $w[$i], $w[$i+1]);
+        $w[$i+1] -= $v;
+        $out += $v;
+        $w[$i] += $v;
+      }
+    }
+    my $done = 1;
+    foreach my $v (@w) {
+      if ($v != $m) {
+        $done = 0;
+        last;
+      }
+    }
+    if ($done) {
+      last;
+    }
+  }
+  return $out;
+}
diff --git a/challenge-192/roger-bell-west/postscript/ch-1.ps b/challenge-192/roger-bell-west/postscript/ch-1.ps
new file mode 100644
index 0000000000..5a6ace974a
--- /dev/null
+++ b/challenge-192/roger-bell-west/postscript/ch-1.ps
@@ -0,0 +1,59 @@
+%!PS
+
+% begin included library code
+% see https://github.com/Firedrake/postscript-libraries/
+/test {
+    /test.count test.count 1 add def
+    {
+        /test.pass test.pass 1 add def
+    } {
+        ( ) print
+        test.count (....) cvs print
+        (-fail) print
+    } ifelse
+} bind def
+
+/test.start {
+    print (:) print
+    /test.pass 0 def
+    /test.count 0 def
+} bind def
+
+/test.end {
+    ( ) print
+    test.count 0 gt {
+        (Passed ) print
+        test.pass (...) cvs print
+        (/) print
+        test.count (...) cvs print
+        ( \() print
+        test.pass 100 mul test.count idiv (...) cvs print
+        (%\)) print
+        (\r\n) print
+    } if
+} bind def
+
+
+% end included library code
+
+/binaryflip {
+    3 dict begin
+    /n exch def
+    /m n def
+    /r 0 def
+    {
+        m 0 eq {
+            exit
+        } if
+        /m m -1 bitshift def
+        /r r 1 add def
+    } loop
+    1 r bitshift 1 sub n sub
+    end
+} bind def
+
+(binaryflip) test.start
+5 binaryflip 2 eq test
+4 binaryflip 3 eq test
+6 binaryflip 1 eq test
+test.end
diff --git a/challenge-192/roger-bell-west/postscript/ch-2.ps b/challenge-192/roger-bell-west/postscript/ch-2.ps
new file mode 100644
index 0000000000..8ae2e0232d
--- /dev/null
+++ b/challenge-192/roger-bell-west/postscript/ch-2.ps
@@ -0,0 +1,103 @@
+%!PS
+
+% begin included library code
+% see https://github.com/Firedrake/postscript-libraries/
+/test {
+    /test.count test.count 1 add def
+    {
+        /test.pass test.pass 1 add def
+    } {
+        ( ) print
+        test.count (....) cvs print
+        (-fail) print
+    } ifelse
+} bind def
+
+/test.end {
+    ( ) print
+    test.count 0 gt {
+        (Passed ) print
+        test.pass (...) cvs print
+        (/) print
+        test.count (...) cvs print
+        ( \() print
+        test.pass 100 mul test.count idiv (...) cvs print
+        (%\)) print
+        (\r\n) print
+    } if
+} bind def
+
+/reduce { % array proc -> value
+    2 dict begin
+    /p exch def
+    /a exch def
+    a 0 get
+    1 1 a length 1 sub {
+        a exch get
+        p
+    } for
+    end
+} bind def
+
+/all { % [a b] proc -> bool
+    1 dict begin
+    /p exch def
+    true exch
+    {
+        p not {
+            pop false
+            exit
+        } if
+    } forall
+    end
+} bind def
+
+/test.start {
+    print (:) print
+    /test.pass 0 def
+    /test.count 0 def
+} bind def
+
+
+% end included library code
+
+/equaldistribution {
+    8 dict begin
+    /list exch def
+    /s list { add } reduce def
+    s list length mod 0 eq {
+        /m s list length idiv def
+        /out 0 def
+        /w [ list aload pop ] def
+        {
+            0 1 w length 2 sub {
+                /i exch def
+                w i get m gt {
+                    /v w i get m sub def
+                    w i 1 add w i 1 add get m add put
+                    /out out v add def
+                    w i m put
+                } if
+                w i get m lt {
+                    /v m w i get sub w i 1 add get min def
+                    w i 1 add w i 1 add get v sub put
+                    /out out v add def
+                    w i w i get v add put
+                } if
+            } for
+            w { m eq } all {
+                exit
+            } if
+        } loop
+        out
+    } {
+        -1
+    } ifelse
+    end
+} bind def
+
+(equaldistribution) test.start
+[ 1 0 5 ] equaldistribution 4 eq test
+[ 0 2 0 ] equaldistribution -1 eq test
+[ 0 3 0 ] equaldistribution 2 eq test
+test.end
diff --git a/challenge-192/roger-bell-west/python/ch-1.py b/challenge-192/roger-bell-west/python/ch-1.py
new file mode 100755
index 0000000000..b4384b5825
--- /dev/null
+++ b/challenge-192/roger-bell-west/python/ch-1.py
@@ -0,0 +1,24 @@
+#! /usr/bin/python3
+
+import unittest
+
+def binaryflip(n):
+  m = n
+  r = 0
+  while m > 0:
+    m >>= 1
+    r += 1
+  return (1 << r) - 1 - n
+
+class TestBinaryflip(unittest.TestCase):
+
+  def test_ex1(self):
+    self.assertEqual(binaryflip(5), 2, 'example 1')
+
+  def test_ex2(self):
+    self.assertEqual(binaryflip(4), 3, 'example 2')
+
+  def test_ex3(self):
+    self.assertEqual(binaryflip(6), 1, 'example 3')
+
+unittest.main()
diff --git a/challenge-192/roger-bell-west/python/ch-2.py b/challenge-192/roger-bell-west/python/ch-2.py
new file mode 100755
index 0000000000..55a41e3843
--- /dev/null
+++ b/challenge-192/roger-bell-west/python/ch-2.py
@@ -0,0 +1,45 @@
+#! /usr/bin/python3
+
+import unittest
+import re
+
+def equaldistribution(list):
+  s = sum(list)
+  if s % len(list) != 0:
+    return -1
+  m = s // len(list)
+  out = 0
+  w = list
+  while True:
+    for i in range(len(list)-1):
+      if w[i] > m:
+        v = w[i] - m
+        w[i+1] += v
+        out += v
+        w[i] = m
+      elif w[i] < m:
+        v = min(m - w[i], w[i+1])
+        w[i+1] -= v
+        out += v
+        w[i] += v
+    done = True
+    for v in w:
+      if v != m:
+        done = False
+        break
+    if done:
+      break
+  return out
+
+class TestEqualdistribution(unittest.TestCase):
+
+  def test_ex1(self):
+    self.assertEqual(equaldistribution([1, 0, 5]), 4, "example 1")
+
+  def test_ex2(self):
+    self.assertEqual(equaldistribution([0, 2, 0]), -1, "example 2")
+
+  def test_ex3(self):
+    self.assertEqual(equaldistribution([0, 3, 0]), 2, "example 3")
+
+unittest.main()
diff --git a/challenge-192/roger-bell-west/raku/ch-1.p6 b/challenge-192/roger-bell-west/raku/ch-1.p6
new file mode 100755
index 0000000000..0bdb113a97
--- /dev/null
+++ b/challenge-192/roger-bell-west/raku/ch-1.p6
@@ -0,0 +1,19 @@
+#! /usr/bin/perl6
+
+use Test;
+
+plan 3;
+
+is(binaryflip(5), 2, 'example 1');
+is(binaryflip(4), 3, 'example 2');
+is(binaryflip(6), 1, 'example 3');
+
+sub binaryflip($n) {
+    my $m = $n;
+    my $r = 0;
+    while ($m > 0) {
+        $m +>= 1;
+        $r++;
+    }
+    return (1 +< $r) - 1 - $n;
+}
diff --git a/challenge-192/roger-bell-west/raku/ch-2.p6 b/challenge-192/roger-bell-west/raku/ch-2.p6
new file mode 100755
index 0000000000..7b216c665d
--- /dev/null
+++ b/challenge-192/roger-bell-west/raku/ch-2.p6
@@ -0,0 +1,38 @@
+#! /usr/bin/perl6
+
+use Test;
+
+plan 3;
+
+is(equaldistribution([1, 0, 5]), 4, 'example 1');
+is(equaldistribution([0, 2, 0]), -1, 'example 2');
+is(equaldistribution([0, 3, 0]), 2, 'example 3');
+
+sub equaldistribution(@list) {
+    my $s = @list.sum;
+    if ($s % @list.elems != 0) {
+        return -1;
+    }
+    my $m = $s div @list.elems;
+    my $out = 0;
+    my @w = @list;
+    while (True) {
+        for (0..@w.elems-2) -> $i {
+            if (@w[$i] > $m) {
+                my $v = @w[$i] - $m;
+                @w[$i+1] += $v;
+                $out += $v;
+                @w[$i] = $m;
+            } elsif (@w[$i] < $m) {
+                my $v = min($m - @w[$i], @w[$i+1]);
+                @w[$i+1] -= $v;
+                $out += $v;
+                @w[$i] += $v;
+            }
+        }
+        if (@w.all == $m) {
+            last;
+        }
+    }
+    return $out;
+}
diff --git a/challenge-192/roger-bell-west/ruby/ch-1.rb b/challenge-192/roger-bell-west/ruby/ch-1.rb
new file mode 100755
index 0000000000..ecf5bc3342
--- /dev/null
+++ b/challenge-192/roger-bell-west/ruby/ch-1.rb
@@ -0,0 +1,30 @@
+#! /usr/bin/ruby
+
+require 'test/unit'
+
+require 'set'
+
+def binaryflip(n)
+  m = n
+  r = 0
+  while (m > 0) do
+    m >>= 1
+    r += 1
+  end
+  return (1 << r) - 1 - n
+end
+
+class TestBinaryflip < Test::Unit::TestCase
+
+  def test_ex1
+    assert_equal(2, binaryflip(5));
+  end
+
+  def test_ex2
+    assert_equal(3, binaryflip(4));
+  end
+
+  def test_ex3
+    assert_equal(1, binaryflip(6));
+  end
+end
diff --git a/challenge-192/roger-bell-west/ruby/ch-2.rb b/challenge-192/roger-bell-west/ruby/ch-2.rb
new file mode 100755
index 0000000000..08b1394ce3
--- /dev/null
+++ b/challenge-192/roger-bell-west/ruby/ch-2.rb
@@ -0,0 +1,47 @@
+#! /usr/bin/ruby
+
+require 'test/unit'
+
+def equaldistribution(list)
+  s = list.sum
+  if s % list.length != 0 then
+    return -1
+  end
+  m = s / list.length
+  out = 0
+  w = list
+  while true do
+    0.upto(w.length-2) do |i|
+      if w[i] > m then
+        v = w[i] - m
+        w[i+1] += v
+        out += v
+        w[i] = m
+      elsif w[i] < m then
+        v = [m - w[i], w[i+1]].min
+        w[i+1] -= v
+        out += v
+        w[i] += v
+      end
+    end
+    if w.all? {|s| s == m} then
+      break
+    end
+  end
+  return out
+end
+
+class TestEqualdistribution < Test::Unit::TestCase
+
+  def test_ex1
+    assert_equal(4, equaldistribution([1, 0, 5]))
+  end
+
+  def test_ex2
+    assert_equal(-1, equaldistribution([0, 2, 0]))
+  end
+
+  def test_ex3
+    assert_equal(2, equaldistribution([0, 3, 0]))
+  end
+end
diff --git a/challenge-192/roger-bell-west/rust/ch-1.rs b/challenge-192/roger-bell-west/rust/ch-1.rs
new file mode 100755
index 0000000000..e93b2c8ebf
--- /dev/null
+++ b/challenge-192/roger-bell-west/rust/ch-1.rs
@@ -0,0 +1,27 @@
+#! /bin/sh
+//usr/bin/env rustc --test $0 -o ${0}x && ./${0}x --nocapture; rm -f ${0}x ; exit
+
+#[test]
+fn test_ex1() {
+    assert_eq!(binaryflip(5), 2);
+}
+
+#[test]
+fn test_ex2() {
+    assert_eq!(binaryflip(4), 3);
+}
+
+#[test]
+fn test_ex3() {
+    assert_eq!(binaryflip(6), 1);
+}
+
+fn binaryflip(n: usize) -> usize {
+    let mut m = n;
+    let mut r = 0;
+    while m > 0 {
+        m >>= 1;
+        r += 1;
+    }
+    (1 << r) - 1 - n
+}
diff --git a/challenge-192/roger-bell-west/rust/ch-2.rs b/challenge-192/roger-bell-west/rust/ch-2.rs
new file mode 100755
index 0000000000..7517d1f1aa
--- /dev/null
+++ b/challenge-192/roger-bell-west/rust/ch-2.rs
@@ -0,0 +1,56 @@
+#! /bin/sh
+//usr/bin/env rustc --test $0 -o ${0}x && ./${0}x --nocapture; rm -f ${0}x ; exit
+
+use std::cmp::min;
+
+#[test]
+fn test_ex1() {
+    assert_eq!(equaldistribution(vec![1, 0, 5]), 4);
+}
+
+#[test]
+fn test_ex2() {
+    assert_eq!(equaldistribution(vec![0, 2, 0]), -1);
+}
+
+#[test]
+fn test_ex3() {
+    assert_eq!(equaldistribution(vec![0, 3, 0]), 2);
+}
+
+fn equaldistribution(list: Vec<isize>) -> isize {
+    let s = list.iter().sum::<isize>();
+    let l = list.len() as isize;
+    if s % l != 0 {
+        return -1;
+    }
+    let m = s / l;
+    let mut out = 0;
+    let mut w = list.clone();
+    loop {
+        for i in 0..w.len() - 1 {
+            if w[i] > m {
+                let v = w[i] - m;
+                w[i + 1] += v;
+                out += v;
+                w[i] = m;
+            } else if w[i] < m {
+                let v = min(m - w[i], w[i + 1]);
+                w[i + 1] -= v;
+                out += v;
+                w[i] += v;
+            }
+        }
+        let mut done = true;
+        for v in &w {
+            if *v != m {
+                done = false;
+                break;
+            }
+        }
+        if done {
+            break;
+        }
+    }
+    out
+}