Merge pull request #8156 from Firedrake/rogerbw-challenge-219

RogerBW solutions for challenge no. 219

19 files changed, 1023 insertions, 0 deletions

diff --git a/challenge-219/roger-bell-west/javascript/ch-1.js b/challenge-219/roger-bell-west/javascript/ch-1.js
new file mode 100755
index 0000000000..de21513378
--- /dev/null
+++ b/challenge-219/roger-bell-west/javascript/ch-1.js
@@ -0,0 +1,51 @@
+#! /usr/bin/node
+
+"use strict"
+
+// by Frank Tan
+// https://stackoverflow.com/questions/38400594/javascript-deep-comparison
+function deepEqual(a,b)
+{
+    if( (typeof a == 'object' && a != null) &&
+        (typeof b == 'object' && b != null) )
+    {
+        var count = [0,0];
+        for( var key in a) count[0]++;
+        for( var key in b) count[1]++;
+        if( count[0]-count[1] != 0) {return false;}
+        for( var key in a)
+        {
+            if(!(key in b) || !deepEqual(a[key],b[key])) {return false;}
+        }
+        for( var key in b)
+        {
+            if(!(key in a) || !deepEqual(b[key],a[key])) {return false;}
+        }
+        return true;
+    }
+    else
+    {
+        return a === b;
+    }
+}
+
+function sortedsquares(lst) {
+    let q = lst.map(x => x * x);
+    q.sort(function(a,b) {
+        return a-b;
+    });
+    return q;
+}
+
+if (deepEqual(sortedsquares([-2, -1, 0, 3, 4]), [0, 1, 4, 9, 16])) {
+  process.stdout.write("Pass");
+} else {
+  process.stdout.write("FAIL");
+}
+process.stdout.write(" ");
+if (deepEqual(sortedsquares([5, -4, -1, 3, 6]), [1, 9, 16, 25, 36])) {
+  process.stdout.write("Pass");
+} else {
+  process.stdout.write("FAIL");
+}
+process.stdout.write("\n");
diff --git a/challenge-219/roger-bell-west/javascript/ch-2.js b/challenge-219/roger-bell-west/javascript/ch-2.js
new file mode 100755
index 0000000000..7aab6ecda1
--- /dev/null
+++ b/challenge-219/roger-bell-west/javascript/ch-2.js
@@ -0,0 +1,46 @@
+#! /usr/bin/node
+
+"use strict"
+
+function travelexpenditure(costs, days0) {
+    let days = days0;
+    days.sort(function(a,b) {
+        return a-b;
+    });
+    const validities = [1, 7, 30];
+    let stack = [];
+    stack.push([0, days]);
+    let cheapest = days.length * costs[0];
+    while (stack.length > 0) {
+        const c = stack.shift();
+        if (c[1].length == 0) {
+            if (c[0] < cheapest) {
+                cheapest = c[0];
+            }
+        } else {
+            if (c[0] >= cheapest) {
+                continue;
+            }
+            const start = c[1][0];
+            for (let i = 0; i <= 2; i++) {
+                const ed = start + validities[i] - 1;
+                let dtd = c[1].filter(x => x > ed);
+                stack.push([c[0] + costs[i], dtd]);
+            }
+        }
+    }
+    return cheapest;
+}
+
+if (travelexpenditure([2, 7, 25], [1, 5, 6, 7, 9, 15]) == 11) {
+  process.stdout.write("Pass");
+} else {
+  process.stdout.write("FAIL");
+}
+process.stdout.write(" ");
+if (travelexpenditure([2, 7, 25], [1, 2, 3, 5, 7, 10, 11, 12, 14, 20, 30, 31]) == 20) {
+  process.stdout.write("Pass");
+} else {
+  process.stdout.write("FAIL");
+}
+process.stdout.write("\n");
diff --git a/challenge-219/roger-bell-west/kotlin/ch-1.kt b/challenge-219/roger-bell-west/kotlin/ch-1.kt
new file mode 100644
index 0000000000..4182f087a9
--- /dev/null
+++ b/challenge-219/roger-bell-west/kotlin/ch-1.kt
@@ -0,0 +1,20 @@
+fun sortedsquares(lst: List<Int>): List<Int> {
+    return lst.map {it * it}.sorted()
+}
+
+fun main() {
+
+    if (sortedsquares(listOf(-2, -1, 0, 3, 4)) == listOf(0, 1, 4, 9, 16)) {
+        print("Pass")
+    } else {
+        print("Fail")
+    }
+    print(" ")
+    if (sortedsquares(listOf(5, -4, -1, 3, 6)) == listOf(1, 9, 16, 25, 36)) {
+        print("Pass")
+    } else {
+        print("Fail")
+    }
+    println("")
+
+}
diff --git a/challenge-219/roger-bell-west/kotlin/ch-2.kt b/challenge-219/roger-bell-west/kotlin/ch-2.kt
new file mode 100644
index 0000000000..f8a485b136
--- /dev/null
+++ b/challenge-219/roger-bell-west/kotlin/ch-2.kt
@@ -0,0 +1,43 @@
+fun travelexpenditure(costs: List<Int>, days0: List<Int>): Int {
+    val days = ArrayList(days0).sorted()
+    val validities = listOf(1, 7, 30)
+    var stack = ArrayDeque<Pair<Int, List<Int>>>()
+    stack.add(Pair(0, days))
+    var cheapest = days.size * costs[0]
+    while (stack.size > 0) {
+        val c = stack.removeFirst()
+        if (c.second.size == 0) {
+            if (c.first < cheapest) {
+                cheapest = c.first
+            }
+        } else {
+            if (c.first >= cheapest) {
+                continue
+            }
+            val start = c.second[0]
+            for (i in 0..2) {
+                val ed = start + validities[i] - 1
+                var dtd = c.second.filter{it > ed}
+                stack.add(Pair(c.first + costs[i], dtd))
+            }
+        }
+    }
+    return cheapest
+}
+
+fun main() {
+
+    if (travelexpenditure(listOf(2, 7, 25), listOf(1, 5, 6, 7, 9, 15)) == 11) {
+        print("Pass")
+    } else {
+        print("Fail")
+    }
+    print(" ")
+    if (travelexpenditure(listOf(2, 7, 25), listOf(1, 2, 3, 5, 7, 10, 11, 12, 14, 20, 30, 31)) == 20) {
+        print("Pass")
+    } else {
+        print("Fail")
+    }
+    println("")
+
+}
diff --git a/challenge-219/roger-bell-west/lua/ch-1.lua b/challenge-219/roger-bell-west/lua/ch-1.lua
new file mode 100755
index 0000000000..241c855e73
--- /dev/null
+++ b/challenge-219/roger-bell-west/lua/ch-1.lua
@@ -0,0 +1,54 @@
+#! /usr/bin/lua
+
+-- by Michael Anderson at
+-- https://stackoverflow.com/questions/8722620/comparing-two-index-tables-by-index-value-in-lua
+-- modified by Roger
+function recursive_compare(t1,t2)
+  -- Use usual comparison first.
+  if t1==t2 then return true end
+  -- We only support non-default behavior for tables
+  if (type(t1)~="table") then return false end
+  -- They better have the same metatables
+  local mt1 = getmetatable(t1)
+  local mt2 = getmetatable(t2)
+  if( not recursive_compare(mt1,mt2) ) then return false end
+  -- Build list of all keys
+  local kk = {}
+  for k1, _ in pairs(t1) do
+     kk[k1] = true
+  end
+  for k2, _ in pairs(t2) do
+     kk[k2] = true
+  end
+  -- Check each key that exists in at least one table
+  for _, k in ipairs(kk) do
+     if (not recursive_compare(t1[k], t2[k])) then
+        return false
+     end
+  end
+  return true
+end
+
+function sortedsquares(lst)
+   local q = {}
+   for _, j in ipairs(lst) do
+      table.insert(q, j * j)
+   end
+   table.sort(q)
+   return q
+end
+
+if recursive_compare(sortedsquares({-2, -1, 0, 3, 4}), {0, 1, 4, 9, 16}) then
+  io.write("Pass")
+else
+  io.write("FAIL")
+end
+io.write(" ")
+
+if recursive_compare(sortedsquares({5, -4, -1, 3, 6}), {1, 9, 16, 25, 36}) then
+  io.write("Pass")
+else
+  io.write("FAIL")
+end
+print("")
+
diff --git a/challenge-219/roger-bell-west/lua/ch-2.lua b/challenge-219/roger-bell-west/lua/ch-2.lua
new file mode 100755
index 0000000000..303ebc51db
--- /dev/null
+++ b/challenge-219/roger-bell-west/lua/ch-2.lua
@@ -0,0 +1,64 @@
+#! /usr/bin/lua
+
+function propersize(t)
+   local l=0
+   for k,v in pairs(t) do
+      l = l + 1
+   end
+   return l
+end
+
+function keys(t)
+   local a = {}
+   for k, v in pairs(t) do
+      table.insert(a, k)
+   end
+   return a
+end
+
+function travelexpenditure(costs, days0)
+   local days = days0
+   table.sort(days)
+   local validities = {1, 7, 30}
+   local stack = {}
+   table.insert(stack, {0, days})
+   local cheapest = #days * costs[1]
+   while #stack > 0 do
+      local c = table.remove(stack, 1)
+      if #(c[2]) == 0 then
+         if c[1] < cheapest then
+            cheapest = c[1]
+         end
+      else
+         if c[1] < cheapest then
+            local start = c[2][1]
+            for i = 1, 3 do
+               local ed = start + validities[i] - 1
+               local dtd = {}
+               for _, j in ipairs(c[2]) do
+                  if j > ed then
+                     table.insert(dtd , j)
+                  end
+               end
+               table.insert(stack, {c[1] + costs[i], dtd})
+            end
+         end
+      end
+   end
+   return cheapest
+end
+
+if travelexpenditure({2, 7, 25}, {1, 5, 6, 7, 9, 15}) == 11 then
+  io.write("Pass")
+else
+  io.write("FAIL")
+end
+io.write(" ")
+
+if travelexpenditure({2, 7, 25}, {1, 2, 3, 5, 7, 10, 11, 12, 14, 20, 30, 31}) == 20 then
+  io.write("Pass")
+else
+  io.write("FAIL")
+end
+print("")
+
diff --git a/challenge-219/roger-bell-west/perl/ch-1.pl b/challenge-219/roger-bell-west/perl/ch-1.pl
new file mode 100755
index 0000000000..9a71315baa
--- /dev/null
+++ b/challenge-219/roger-bell-west/perl/ch-1.pl
@@ -0,0 +1,14 @@
+#! /usr/bin/perl
+
+use strict;
+use warnings;
+use experimental 'signatures';
+
+use Test::More tests => 2;
+
+is_deeply(sortedsquares([-2, -1, 0, 3, 4]), [0, 1, 4, 9, 16], 'example 1');
+is_deeply(sortedsquares([5, -4, -1, 3, 6]), [1, 9, 16, 25, 36], 'example 2');
+
+sub sortedsquares($lst) {
+  return [sort {$a <=> $b} map{$_ * $_} @{$lst}];
+}
diff --git a/challenge-219/roger-bell-west/perl/ch-2.pl b/challenge-219/roger-bell-west/perl/ch-2.pl
new file mode 100755
index 0000000000..8d97e17bf9
--- /dev/null
+++ b/challenge-219/roger-bell-west/perl/ch-2.pl
@@ -0,0 +1,38 @@
+#! /usr/bin/perl
+
+use strict;
+use warnings;
+use experimental 'signatures';
+
+use Test::More tests => 2;
+
+is(travelexpenditure([2, 7, 25], [1, 5, 6, 7, 9, 15]), 11, 'example 1');
+is(travelexpenditure([2, 7, 25], [1, 2, 3, 5, 7, 10, 11, 12, 14, 20, 30, 31]), 20, 'example 2');
+
+sub travelexpenditure($costs, $days0) {
+  my @days = sort {$a <=> $b} @{$days0};
+  my @validities = (1, 7, 30);
+  my @stack;
+  push @stack, {costdone => 0, daystodo => \@days};
+  my $cheapest = (scalar @days) * $costs->[0];
+  while (scalar @stack > 0) {
+    my $c = shift @stack;
+    if (scalar @{$c->{daystodo}} == 0) {
+      if ($c->{costdone} < $cheapest) {
+        $cheapest = $c->{costdone};
+      }
+    } else {
+      if ($c->{costdone} >= $cheapest) {
+        next;
+      }
+      my $start = $c->{daystodo}[0];
+      foreach my $i (0..2) {
+        my $ed = $start + $validities[$i] - 1;
+        my @dtd = grep {$_ > $ed} @{$c->{daystodo}};
+        push @stack,{costdone => $c->{costdone} + $costs->[$i],
+                     daystodo => \@dtd};
+      }
+    }
+  }
+  return $cheapest;
+}
diff --git a/challenge-219/roger-bell-west/postscript/ch-1.ps b/challenge-219/roger-bell-west/postscript/ch-1.ps
new file mode 100644
index 0000000000..3852d988e1
--- /dev/null
+++ b/challenge-219/roger-bell-west/postscript/ch-1.ps
@@ -0,0 +1,203 @@
+%!PS
+
+% begin included library code
+% see https://codeberg.org/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
+
+/quicksort.main { % lo hi -> (null)
+    3 dict begin
+    /hi exch def
+    /lo exch def
+    /xit false def
+    lo 0 lt {
+        /xit true def
+    } if
+    hi 0 lt {
+        /xit true def
+    } if
+    lo hi ge {
+        /xit true def
+    } if
+    xit not {
+        /p quicksort.partition def
+        lo p quicksort.main
+        p 1 add hi quicksort.main
+    } if
+    end
+} bind def
+
+/quicksort.with_comparator { % [ a c b ] { comparator } -> [ a b c ]
+    2 dict begin
+    /cmp exch def
+    /arr exch def
+    arr length 0 gt {
+        0 arr length 1 sub quicksort.main
+    } if
+    arr
+    end
+} bind def
+
+/quicksort {
+    { quicksort.cmp } quicksort.with_comparator
+} 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
+
+/quicksort.partition {
+    3 dict begin
+    /pivot arr hi lo add 2 idiv get def
+    /i lo 1 sub def
+    /j hi 1 add def
+    {
+        {
+            /i i 1 add def
+            arr i get pivot cmp 0 ge {
+                exit
+            } if
+        } loop
+        {
+            /j j 1 sub def
+            arr j get pivot cmp 0 le {
+                exit
+            } if
+        } loop
+        i j ge {
+            j
+            exit
+        } if
+        i j quicksort.swap
+    } loop
+    end
+} bind def
+
+/deepeq {
+    2 dict begin
+    /a exch def
+    /b exch def
+    a type b type eq {
+        a type /dicttype eq {
+            a length b length eq {
+                <<
+                    a {
+                        pop
+                        true
+                    } forall
+                    b {
+                        pop
+                        true
+                    } forall
+                >>
+                true exch
+                {
+                    pop
+                    dup a exch known {
+                        dup b exch known {
+                            dup a exch get exch b exch get deepeq not {
+                                pop false
+                            } if
+                        } {
+                            false
+                        } ifelse
+                    } {
+                        false
+                    } ifelse
+                } forall
+            } {
+                false
+            } ifelse
+        } {
+            a type dup /arraytype eq exch /stringtype eq or {
+                a length b length eq {
+                    true
+                    0 1 a length 1 sub {
+                        dup a exch get exch b exch get deepeq not {
+                            pop false
+                            exit
+                        } if
+                    } for
+                } {
+                    false
+                } ifelse
+            } {
+                a b eq
+            } ifelse
+        } ifelse
+    } {
+        false
+    } ifelse
+    end
+} bind def
+
+/test.start {
+    print (:) print
+    /test.pass 0 def
+    /test.count 0 def
+} bind def
+
+/map { % array proc -> array
+    2 dict begin
+    /p exch def
+    [ exch
+      {
+          p
+      } forall
+    ]
+    end
+} bind def
+
+/quicksort.swap {
+    2 dict begin
+    /bi exch def
+    /ai exch def
+    arr ai get
+    arr bi get
+    arr exch ai exch put
+    arr exch bi exch put
+    end
+} bind def
+
+/quicksort.cmp {
+    2 copy
+    lt {
+        pop pop -1
+    } {
+        gt {
+            1
+        } {
+            0
+        } ifelse
+    } ifelse
+} bind def
+
+
+% end included library code
+
+/sortedsquares {
+    { dup mul } map quicksort
+} bind def
+
+(sortedsquares) test.start
+[-2 -1 0 3 4] sortedsquares [0 1 4 9 16] deepeq test
+[5 -4 -1 3 6] sortedsquares [1 9 16 25 36] deepeq test
+test.end
diff --git a/challenge-219/roger-bell-west/postscript/ch-2.ps b/challenge-219/roger-bell-west/postscript/ch-2.ps
new file mode 100644
index 0000000000..ce9dcb6550
--- /dev/null
+++ b/challenge-219/roger-bell-west/postscript/ch-2.ps
@@ -0,0 +1,188 @@
+%!PS
+
+% begin included library code
+% see https://codeberg.org/Firedrake/postscript-libraries/
+/filter { % array proc(bool) -> array
+    1 dict begin
+    /p exch def
+    [ exch
+      {
+          dup p not
+          {
+              pop
+          } if
+      } forall
+    ]
+    end
+} bind def
+
+/quicksort {
+    { quicksort.cmp } quicksort.with_comparator
+} bind def
+
+/apush.right { % [a b] c -> [a b c]
+    exch
+    [ exch aload length 2 add -1 roll ]
+} bind def
+
+/test.start {
+    print (:) print
+    /test.pass 0 def
+    /test.count 0 def
+} bind def
+
+/quicksort.partition {
+    3 dict begin
+    /pivot arr hi lo add 2 idiv get def
+    /i lo 1 sub def
+    /j hi 1 add def
+    {
+        {
+            /i i 1 add def
+            arr i get pivot cmp 0 ge {
+                exit
+            } if
+        } loop
+        {
+            /j j 1 sub def
+            arr j get pivot cmp 0 le {
+                exit
+            } if
+        } loop
+        i j ge {
+            j
+            exit
+        } if
+        i j quicksort.swap
+    } loop
+    end
+} 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
+
+/quicksort.cmp {
+    2 copy
+    lt {
+        pop pop -1
+    } {
+        gt {
+            1
+        } {
+            0
+        } ifelse
+    } ifelse
+} bind def
+
+/quicksort.with_comparator { % [ a c b ] { comparator } -> [ a b c ]
+    2 dict begin
+    /cmp exch def
+    /arr exch def
+    arr length 0 gt {
+        0 arr length 1 sub quicksort.main
+    } if
+    arr
+    end
+} bind def
+
+/apop.left { % [a b c] -> [b c] a
+    dup 0 get exch
+    [ exch aload length -1 roll pop ] exch
+} bind def
+
+/quicksort.swap {
+    2 dict begin
+    /bi exch def
+    /ai exch def
+    arr ai get
+    arr bi get
+    arr exch ai exch put
+    arr exch bi exch put
+    end
+} bind def
+
+/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
+
+/quicksort.main { % lo hi -> (null)
+    3 dict begin
+    /hi exch def
+    /lo exch def
+    /xit false def
+    lo 0 lt {
+        /xit true def
+    } if
+    hi 0 lt {
+        /xit true def
+    } if
+    lo hi ge {
+        /xit true def
+    } if
+    xit not {
+        /p quicksort.partition def
+        lo p quicksort.main
+        p 1 add hi quicksort.main
+    } if
+    end
+} bind def
+
+
+% end included library code
+
+/travelexpenditure {
+    9 dict begin
+    quicksort /days exch def
+    /costs exch def
+    /validities [ 1 7 30 ] def
+    /stack [ [ 0 days ] ] def
+    /cheapest days length costs 0 get mul def
+    {
+        stack length 0 eq {
+            exit
+        } if
+        stack apop.left /c exch def /stack exch def
+        c 1 get length 0 eq {
+            c 0 get cheapest lt {
+                /cheapest c 0 get def
+            } if
+        } {
+            c 0 get cheapest lt {
+                /start c 1 get 0 get def
+                0 1 2 {
+                    /i exch def
+                    /ed start validities i get add 1 sub def
+                    /stack stack [
+                        c 0 get costs i get add
+                        c 1 get { ed gt } filter
+                    ] apush.right def
+                } for
+            } if
+        } ifelse
+    } loop
+    cheapest
+    end
+} bind def
+
+(travelexpenditure) test.start
+[2 7 25] [1 5 6 7 9 15] travelexpenditure 11 eq test
+[2 7 25] [1 2 3 5 7 10 11 12 14 20 30 31] travelexpenditure 20 eq test
+test.end
diff --git a/challenge-219/roger-bell-west/python/ch-1.py b/challenge-219/roger-bell-west/python/ch-1.py
new file mode 100755
index 0000000000..b6737234e7
--- /dev/null
+++ b/challenge-219/roger-bell-west/python/ch-1.py
@@ -0,0 +1,18 @@
+#! /usr/bin/python3
+
+def sortedsquares(lst):
+  q = [i * i for i in lst]
+  q.sort()
+  return q
+
+import unittest
+
+class TestSortedsquares(unittest.TestCase):
+
+  def test_ex1(self):
+    self.assertEqual(sortedsquares([-2, -1, 0, 3, 4]), [0, 1, 4, 9, 16], 'example 1')
+
+  def test_ex2(self):
+    self.assertEqual(sortedsquares([5, -4, -1, 3, 6]), [1, 9, 16, 25, 36], 'example 2')
+
+unittest.main()
diff --git a/challenge-219/roger-bell-west/python/ch-2.py b/challenge-219/roger-bell-west/python/ch-2.py
new file mode 100755
index 0000000000..d747e7ad69
--- /dev/null
+++ b/challenge-219/roger-bell-west/python/ch-2.py
@@ -0,0 +1,36 @@
+#! /usr/bin/python3
+
+from collections import deque
+
+def travelexpenditure(costs, days0):
+  days = sorted(days0)
+  validities = [1, 7, 30]
+  stack = deque()
+  stack.append([0, days])
+  cheapest = len(days) * costs[0]
+  while len(stack) > 0:
+    c = stack.popleft()
+    if len(c[1]) == 0:
+      if c[0] < cheapest:
+        cheapest = c[0]
+    else:
+      if c[0] >= cheapest:
+        continue
+      start = c[1][0]
+      for i in range(3):
+        end = start + validities[i] - 1
+        dtd = list(filter(lambda x: x > end, c[1]))
+        stack.append([c[0] + costs[i], dtd])
+  return cheapest
+
+import unittest
+
+class TestTravelexpenditure(unittest.TestCase):
+
+  def test_ex1(self):
+    self.assertEqual(travelexpenditure([2, 7, 25], [1, 5, 6, 7, 9, 15]), 11, 'example 1')
+
+  def test_ex2(self):
+    self.assertEqual(travelexpenditure([2, 7, 25], [1, 2, 3, 5, 7, 10, 11, 12, 14, 20, 30, 31]), 20, 'example 2')
+
+unittest.main()
diff --git a/challenge-219/roger-bell-west/raku/ch-1.p6 b/challenge-219/roger-bell-west/raku/ch-1.p6
new file mode 100755
index 0000000000..e6f6c68c72
--- /dev/null
+++ b/challenge-219/roger-bell-west/raku/ch-1.p6
@@ -0,0 +1,12 @@
+#! /usr/bin/raku
+
+use Test;
+
+plan 2;
+
+is-deeply(sortedsquares([-2, -1, 0, 3, 4]), [0, 1, 4, 9, 16], 'example 1');
+is-deeply(sortedsquares([5, -4, -1, 3, 6]), [1, 9, 16, 25, 36], 'example 2');
+
+sub sortedsquares(@lst) {
+    return @lst.map({$_ * $_}).sort({$^a <=> $^b}).Array;
+}
diff --git a/challenge-219/roger-bell-west/raku/ch-2.p6 b/challenge-219/roger-bell-west/raku/ch-2.p6
new file mode 100755
index 0000000000..6a450d6c54
--- /dev/null
+++ b/challenge-219/roger-bell-west/raku/ch-2.p6
@@ -0,0 +1,36 @@
+#! /usr/bin/raku
+
+use Test;
+
+plan 2;
+
+is(travelexpenditure([2, 7, 25], [1, 5, 6, 7, 9, 15]), 11, 'example 1');
+is(travelexpenditure([2, 7, 25], [1, 2, 3, 5, 7, 10, 11, 12, 14, 20, 30, 31]), 20, 'example 2');
+
+sub travelexpenditure(@costs, @days0) {
+    my @days = @days0.sort({$^a <=> $^b});
+    my @validities = [1, 7, 30];
+    my @stack;
+    @stack.push({costdone => 0, daystodo => @days});
+    my $cheapest = @days.elems * @costs[0];
+    while (@stack.elems > 0) {
+        my %c = @stack.shift;
+        if (%c{'daystodo'}.elems == 0) {
+            if (%c{'costdone'} < $cheapest) {
+                $cheapest = %c{'costdone'};
+            }
+        } else {
+            if (%c{'costdone'} >= $cheapest) {
+                next;
+            }
+            my $start = %c{'daystodo'}[0];
+            for 0..2 -> $i {
+                my $ed = $start + @validities[$i] - 1;
+                my @dtd = %c{'daystodo'}.grep({$_ > $ed});
+                @stack.push({costdone => %c{'costdone'} + @costs[$i],
+                                                        daystodo => @dtd});
+            }
+        }
+    }
+    return $cheapest;
+}
diff --git a/challenge-219/roger-bell-west/ruby/ch-1.rb b/challenge-219/roger-bell-west/ruby/ch-1.rb
new file mode 100755
index 0000000000..fc5ba50a46
--- /dev/null
+++ b/challenge-219/roger-bell-west/ruby/ch-1.rb
@@ -0,0 +1,19 @@
+#! /usr/bin/ruby
+
+def sortedsquares(lst)
+  return lst.collect {|x| x * x}.sort
+end
+
+require 'test/unit'
+
+class TestSortedsquares < Test::Unit::TestCase
+
+  def test_ex1
+    assert_equal([0, 1, 4, 9, 16], sortedsquares([-2, -1, 0, 3, 4]))
+  end
+
+  def test_ex2
+    assert_equal([1, 9, 16, 25, 36], sortedsquares([5, -4, -1, 3, 6]))
+  end
+
+end
diff --git a/challenge-219/roger-bell-west/ruby/ch-2.rb b/challenge-219/roger-bell-west/ruby/ch-2.rb
new file mode 100755
index 0000000000..e4d72b318a
--- /dev/null
+++ b/challenge-219/roger-bell-west/ruby/ch-2.rb
@@ -0,0 +1,42 @@
+#! /usr/bin/ruby
+
+def travelexpenditure(costs, days0)
+  days = days0.sort
+  validities = [1, 7, 30]
+  stack = []
+  stack.push([0, days])
+  cheapest = days.length * costs[0]
+  while stack.length > 0 do
+    c = stack.shift
+    if c[1].length == 0 then
+      if c[0] < cheapest then
+        cheapest = c[0]
+      end
+    else
+      if c[0] >= cheapest then
+        next
+      end
+      start = c[1][0]
+      0.upto(2) do |i|
+        ed = start + validities[i] - 1
+        dtd = c[1].find_all {|x| x > ed}
+        stack.push([c[0] + costs[i], dtd])
+      end
+    end
+  end
+  return cheapest
+end
+
+require 'test/unit'
+
+class TestTravelexpenditure < Test::Unit::TestCase
+
+  def test_ex1
+    assert_equal(11, travelexpenditure([2, 7, 25], [1, 5, 6, 7, 9, 15]))
+  end
+
+  def test_ex2
+    assert_equal(20, travelexpenditure([2, 7, 25], [1, 2, 3, 5, 7, 10, 11, 12, 14, 20, 30, 31]))
+  end
+
+end
diff --git a/challenge-219/roger-bell-west/rust/ch-1.rs b/challenge-219/roger-bell-west/rust/ch-1.rs
new file mode 100755
index 0000000000..5bfa669c67
--- /dev/null
+++ b/challenge-219/roger-bell-west/rust/ch-1.rs
@@ -0,0 +1,18 @@
+#! /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!(sortedsquares(vec![-2, -1, 0, 3, 4]), vec![0, 1, 4, 9, 16]);
+}
+
+#[test]
+fn test_ex2() {
+    assert_eq!(sortedsquares(vec![5, -4, -1, 3, 6]), vec![1, 9, 16, 25, 36]);
+}
+
+fn sortedsquares(lst: Vec<i32>) -> Vec<i32> {
+    let mut q = lst.iter().map(|i| i * i).collect::<Vec<i32>>();
+    q.sort();
+    q
+}
diff --git a/challenge-219/roger-bell-west/rust/ch-2.rs b/challenge-219/roger-bell-west/rust/ch-2.rs
new file mode 100755
index 0000000000..9a0ac721e6
--- /dev/null
+++ b/challenge-219/roger-bell-west/rust/ch-2.rs
@@ -0,0 +1,61 @@
+#! /bin/sh
+//usr/bin/env rustc --test $0 -o ${0}x && ./${0}x --nocapture; rm -f ${0}x ; exit
+
+use std::collections::VecDeque;
+
+#[test]
+fn test_ex1() {
+    assert_eq!(travelexpenditure(vec![2, 7, 25], vec![1, 5, 6, 7, 9, 15]), 11);
+}
+
+#[test]