Merge pull request #9299 from Firedrake/rogerbw-challenge-249

RogerBW solutions for challenge no. 249

21 files changed, 1264 insertions, 0 deletions

diff --git a/challenge-249/roger-bell-west/javascript/ch-1.js b/challenge-249/roger-bell-west/javascript/ch-1.js
new file mode 100755
index 0000000000..6b39470cdd
--- /dev/null
+++ b/challenge-249/roger-bell-west/javascript/ch-1.js
@@ -0,0 +1,59 @@
+#! /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 shortestdistance(a0) {
+    if (a0.length % 2 != 0) {
+        return [];
+    }
+    let a = a0;
+    a.sort();
+    let out = [];
+    for (let i = 0; i < a.length; i += 2) {
+        if (a[i] != a[i + 1]) {
+            return [];
+        }
+        out.push([a[i], a[i]]);
+    }
+    return out;
+}
+
+if (deepEqual(shortestdistance([3, 2, 3, 2, 2, 2]), [[2, 2], [2, 2], [3, 3]])) {
+  process.stdout.write("Pass");
+} else {
+  process.stdout.write("FAIL");
+}
+process.stdout.write(" ");
+if (deepEqual(shortestdistance([1, 2, 3, 4]), [])) {
+  process.stdout.write("Pass");
+} else {
+  process.stdout.write("FAIL");
+}
+process.stdout.write("\n");
diff --git a/challenge-249/roger-bell-west/javascript/ch-2.js b/challenge-249/roger-bell-west/javascript/ch-2.js
new file mode 100755
index 0000000000..4dd1690970
--- /dev/null
+++ b/challenge-249/roger-bell-west/javascript/ch-2.js
@@ -0,0 +1,71 @@
+#! /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 distringmatch(a) {
+    let v = 1 << (a.length - 1);
+    let wv = v << 1;
+    let out = [wv];
+    for (const c of a) {
+        if (c == 'I') {
+            wv += v;
+        } else {
+            wv -= v;
+        }
+        v >>= 1;
+        out.push(wv);
+    }
+    let q = [...out];
+    q.sort(function(a,b) {
+        return a-b;
+    });
+    let c = new Map;
+    q.forEach((v, i) => {c.set(v, i)});
+    return out.map(x => c.get(x));
+}
+
+if (deepEqual(distringmatch('IDID'), [0, 4, 1, 3, 2])) {
+  process.stdout.write("Pass");
+} else {
+  process.stdout.write("FAIL");
+}
+process.stdout.write(" ");
+if (deepEqual(distringmatch('III'), [0, 1, 2, 3])) {
+  process.stdout.write("Pass");
+} else {
+  process.stdout.write("FAIL");
+}
+process.stdout.write(" ");
+if (deepEqual(distringmatch('DDI'), [3, 2, 0, 1])) {
+  process.stdout.write("Pass");
+} else {
+  process.stdout.write("FAIL");
+}
+process.stdout.write("\n");
diff --git a/challenge-249/roger-bell-west/kotlin/ch-1.kt b/challenge-249/roger-bell-west/kotlin/ch-1.kt
new file mode 100644
index 0000000000..c0bae85bf8
--- /dev/null
+++ b/challenge-249/roger-bell-west/kotlin/ch-1.kt
@@ -0,0 +1,32 @@
+fun shortestdistance(a0: List<Int>): List<List<Int>> {
+    if (a0.size % 2 != 0) {
+        return emptyList<List<Int>>()
+    }
+    var a = ArrayList(a0)
+        a.sort()
+    var out = ArrayList<List<Int>>()
+    for (t in a.chunked(2)) {
+        if (t[0] != t[1]) {
+            return emptyList<List<Int>>()
+        }
+        out.add(listOf(t[0], t[0]))
+    }
+    return out.toList()
+}
+
+fun main() {
+
+    if (shortestdistance(listOf(3, 2, 3, 2, 2, 2)) == listOf(listOf(2, 2), listOf(2, 2), listOf(3, 3))) {
+        print("Pass")
+    } else {
+        print("Fail")
+    }
+    print(" ")
+    if (shortestdistance(listOf(1, 2, 3, 4)) == emptyList<Int>()) {
+        print("Pass")
+    } else {
+        print("Fail")
+    }
+    println("")
+
+}
diff --git a/challenge-249/roger-bell-west/kotlin/ch-2.kt b/challenge-249/roger-bell-west/kotlin/ch-2.kt
new file mode 100644
index 0000000000..8338b31034
--- /dev/null
+++ b/challenge-249/roger-bell-west/kotlin/ch-2.kt
@@ -0,0 +1,45 @@
+fun distringmatch(a: String): List<Int> {
+    var v = 1 shl (a.length - 1)
+    var wv = v shl 1
+    var out = ArrayList<Int>()
+    var q = ArrayList<Int>()
+    out.add(wv)
+    q.add(wv)
+    for (c in a) {
+        if (c == 'I') {
+            wv += v
+        } else {
+            wv -= v
+        }
+        v = v shr 1
+        out.add(wv)
+        q.add(wv)
+    }
+    q.sort()
+    var c = mutableMapOf<Int, Int>()
+    q.forEachIndexed {i, n -> c.put(n, i)}
+    return out.map{c.getValue(it)}.toList()
+}
+
+fun main() {
+
+    if (distringmatch("IDID") == listOf(0, 4, 1, 3, 2)) {
+        print("Pass")
+    } else {
+        print("Fail")
+    }
+    print(" ")
+    if (distringmatch("III") == listOf(0, 1, 2, 3)) {
+        print("Pass")
+    } else {
+        print("Fail")
+    }
+    print(" ")
+    if (distringmatch("DDI") == listOf(3, 2, 0, 1)) {
+        print("Pass")
+    } else {
+        print("Fail")
+    }
+    println("")
+
+}
diff --git a/challenge-249/roger-bell-west/lua/ch-1.lua b/challenge-249/roger-bell-west/lua/ch-1.lua
new file mode 100755
index 0000000000..111457de6f
--- /dev/null
+++ b/challenge-249/roger-bell-west/lua/ch-1.lua
@@ -0,0 +1,61 @@
+#! /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 shortestdistance(a0)
+   if #a0 % 2 ~= 0 then
+      return {}
+   end
+   local a = a0
+   table.sort(a)
+   local out = {}
+   for i = 1, #a, 2 do
+      if a[i] ~= a[i+1] then
+         return {}
+      end
+      table.insert(out, {a[i], a[i]})
+   end
+   return out
+end
+
+if recursive_compare(shortestdistance({3, 2, 3, 2, 2, 2}), {{2, 2}, {2, 2}, {3, 3}}) then
+  io.write("Pass")
+else
+  io.write("FAIL")
+end
+io.write(" ")
+
+if recursive_compare(shortestdistance({1, 2, 3, 4}), {}) then
+  io.write("Pass")
+else
+  io.write("FAIL")
+end
+print("")
+
diff --git a/challenge-249/roger-bell-west/lua/ch-2.lua b/challenge-249/roger-bell-west/lua/ch-2.lua
new file mode 100755
index 0000000000..4ce75b8aff
--- /dev/null
+++ b/challenge-249/roger-bell-west/lua/ch-2.lua
@@ -0,0 +1,79 @@
+#! /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 distringmatch(a)
+   local v = 1 << (#a - 1)
+   local wv = v << 1
+   local out = {wv}
+   local r = {wv}
+   for c in string.gmatch(a, ".") do
+      if c == "I" then
+         wv = wv + v
+      else
+         wv = wv - v
+      end
+      v = v >> 1
+      table.insert(out, wv)
+      table.insert(r, wv)
+   end
+   table.sort(r)
+   local c = {}
+   for i = 1, #r do
+      c[r[i]] = i
+   end
+   local o = {}
+   for _, n in ipairs(out) do
+      table.insert(o, c[n])
+   end
+   return o
+end
+
+if recursive_compare(distringmatch("IDID"), {0, 4, 1, 3, 2}) then
+  io.write("Pass")
+else
+  io.write("FAIL")
+end
+io.write(" ")
+
+if recursive_compare(distringmatch("III"), {0, 1, 2, 3}) then
+  io.write("Pass")
+else
+  io.write("FAIL")
+end
+io.write(" ")
+
+if recursive_compare(distringmatch("DDI"), {3, 2, 0, 1}) then
+  io.write("Pass")
+else
+  io.write("FAIL")
+end
+print("")
+
diff --git a/challenge-249/roger-bell-west/perl/ch-1.pl b/challenge-249/roger-bell-west/perl/ch-1.pl
new file mode 100755
index 0000000000..ca7bc936a5
--- /dev/null
+++ b/challenge-249/roger-bell-west/perl/ch-1.pl
@@ -0,0 +1,25 @@
+#! /usr/bin/perl
+
+use strict;
+use warnings;
+use experimental 'signatures';
+
+use Test::More tests => 2;
+
+is_deeply(shortestdistance([3, 2, 3, 2, 2, 2]), [[2, 2], [2, 2], [3, 3]], 'example 1');
+is_deeply(shortestdistance([1, 2, 3, 4]), [], 'example 2');
+
+sub shortestdistance($a0) {
+  if (scalar @{$a0} % 2 != 0) {
+    return [];
+  }
+  my @a = sort {$a <=> $b} @{$a0};
+  my @out;
+  for (my $i = 0; $i < scalar @a; $i+=2) {
+    if ($a[$i] != $a[$i+1]) {
+      return [];
+    }
+    push @out,[$a[$i], $a[$i]];
+  }
+  return \@out;
+}
diff --git a/challenge-249/roger-bell-west/perl/ch-2.pl b/challenge-249/roger-bell-west/perl/ch-2.pl
new file mode 100755
index 0000000000..92aba07749
--- /dev/null
+++ b/challenge-249/roger-bell-west/perl/ch-2.pl
@@ -0,0 +1,29 @@
+#! /usr/bin/perl
+
+use strict;
+use warnings;
+use experimental 'signatures';
+
+use Test::More tests => 3;
+
+is_deeply(distringmatch('IDID'), [0, 4, 1, 3, 2], 'example 1');
+is_deeply(distringmatch('III'), [0, 1, 2, 3], 'example 2');
+is_deeply(distringmatch('DDI'), [3, 2, 0, 1], 'example 3');
+
+sub distringmatch($a) {
+  my $v = 1 << (length($a) - 1);
+  my $wv = $v << 1;
+  my @out = ($wv);
+  foreach my $c (split '', $a) {
+    if ($c eq 'I') {
+      $wv += $v
+    } else {
+      $wv -= $v;
+    }
+    $v >>= 1;
+    push @out, $wv;
+  }
+  my @r = sort{$::a <=> $::b} @out;
+  my %c = map {$r[$_] => $_} (0..$#r);
+  return [map{$c{$_}} @out];
+}
diff --git a/challenge-249/roger-bell-west/postscript/ch-1.ps b/challenge-249/roger-bell-west/postscript/ch-1.ps
new file mode 100644
index 0000000000..e6ffb359ec
--- /dev/null
+++ b/challenge-249/roger-bell-west/postscript/ch-1.ps
@@ -0,0 +1,215 @@
+%!PS
+
+% begin included library code
+% see https://codeberg.org/Firedrake/postscript-libraries/
+/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
+
+/test.start {
+    print (:) print
+    /test.pass 0 def
+    /test.count 0 def
+} 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.cmp {
+    2 copy
+    lt {
+        pop pop -1
+    } {
+        gt {
+            1
+        } {
+            0
+        } ifelse
+    } ifelse
+} 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.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
+
+/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 {
+    /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.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
+
+
+% end included library code
+
+/shortestdistance {
+    0 dict begin
+    /a exch def
+    1 {
+        a length 2 mod 0 ne {
+            [] exit
+        } if
+        /fail false def
+        /a a quicksort def
+        [
+            0 2 a length 2 sub {
+                /i exch def
+                a i get a i 1 add get ne {
+                    fail true def
+                    exit
+                } if
+                [ a i get dup ]
+            } for
+        ]
+        fail {
+            pop
+            []
+        } if
+    } repeat
+    end
+} bind def
+
+(shortestdistance) test.start
+[3 2 3 2 2 2] shortestdistance [[2 2] [2 2] [3 3]] deepeq test
+[1 2 3 4] shortestdistance [] deepeq test
+test.end
diff --git a/challenge-249/roger-bell-west/postscript/ch-2.ps b/challenge-249/roger-bell-west/postscript/ch-2.ps
new file mode 100644
index 0000000000..4b834a76b9
--- /dev/null
+++ b/challenge-249/roger-bell-west/postscript/ch-2.ps
@@ -0,0 +1,276 @@
+%!PS
+
+% begin included library code
+% see https://codeberg.org/Firedrake/postscript-libraries/
+/quicksort {
+    { quicksort.cmp } quicksort.with_comparator
+} bind def
+
+/enumerate.array {
+    1 dict begin
+    /a exch def
+    [
+      0 1 a length 1 sub {
+          [ exch dup a exch get ]
+      } for
+    ]
+    end
+} 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
+
+/deepcopy {
+    2 dict begin
+    /a exch def
+    a type /dicttype eq {
+        <<
+            a keys {
+                /k exch def
+                k
+                a k get deepcopy
+            } forall
+        >>
+    } {
+        a type /arraytype eq {
+            [
+                a {
+                    deepcopy
+                } forall
+            ]
+        } {
+            a type /stringtype eq {
+                a dup length string cvs
+            } {
+                a
+            } ifelse
+        } ifelse
+    } ifelse
+    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
+
+/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
+
+/keys { % dict -> array of dict keys
+    [ exch
+      {
+          pop
+      } forall
+    ]
+} 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
+
+/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
+
+/map { % array proc -> array
+    2 dict begin
+    /p exch def
+    [ exch
+      {
+          p
+      } forall
+    ]
+    end
+} bind def
+
+/quicksort.cmp {
+    2 copy
+    lt {
+        pop pop -1
+    } {
+        gt {
+            1
+        } {
+            0
+        } ifelse
+    } ifelse
+} 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
+
+
+% end included library code
+
+/distringmatch {
+    0 dict begin
+    /a exch def
+    /v 1 a length 1 sub bitshift def
+    /wv v 1 bitshift def
+    /out [
+        wv
+        a {
+            73 eq {
+                /wv wv v add def
+            } {
+                /wv wv v sub def
+            } ifelse
+            /v v -1 bitshift def
+            wv
+        } forall
+    ] def
+    /c <<
+           out deepcopy
+           quicksort
+           enumerate.array
+           { aload pop exch } map
+           aload pop
+       >> def
+    out { c exch get } map
+    end
+} bind def
+
+(distringmatch) test.start
+(IDID) distringmatch [0 4 1 3 2] deepeq test
+(III) distringmatch [0 1 2 3] deepeq test
+(DDI) distringmatch [3 2 0 1] deepeq test
+test.end
diff --git a/challenge-249/roger-bell-west/python/ch-1.py b/challenge-249/roger-bell-west/python/ch-1.py
new file mode 100755
index 0000000000..e086773409
--- /dev/null
+++ b/challenge-249/roger-bell-west/python/ch-1.py
@@ -0,0 +1,25 @@
+#! /usr/bin/python3
+
+def shortestdistance(a0):
+  if len(a0) % 2 != 0:
+    return []
+  a = a0
+  a.sort()
+  out = []
+  for i in range(0, len(a), 2):
+    if a[i] != a[i+1]:
+      return []
+    out.append([a[i], a[i]])
+  return out
+
+import unittest
+
+class TestShortestdistance(unittest.TestCase):
+
+  def test_ex1(self):
+    self.assertEqual(shortestdistance([3, 2, 3, 2, 2, 2]), [[2, 2], [2, 2], [3, 3]], 'example 1')
+
+  def test_ex2(self):
+    self.assertEqual(shortestdistance([1, 2, 3, 4]), [], 'example 2')
+
+unittest.main()
diff --git a/challenge-249/roger-bell-west/python/ch-2.py b/challenge-249/roger-bell-west/python/ch-2.py
new file mode 100755
index 0000000000..a242036ab7
--- /dev/null
+++ b/challenge-249/roger-bell-west/python/ch-2.py
@@ -0,0 +1,35 @@
+#! /usr/bin/python3
+
+def distringmatch(a):
+  v = 1 << (len(a) - 1)
+  wv = v << 1
+  out = [wv]
+  for c in a:
+    if c == "I":
+      wv += v
+    else:
+      wv -= v
+    v >>= 1
+    out.append(wv)
+  c = dict()
+  q = out.copy()
+  q.sort()
+  for i, v in enumerate(q):
+    c[v] = i
+  return [c[v] for v in out]
+      
+
+import unittest
+
+class TestDistringmatch(unittest.TestCase):
+
+  def test_ex1(self):
+    self.assertEqual(distringmatch("IDID"), [0, 4, 1, 3, 2], 'example 1')
+
+  def test_ex2(self):
+    self.assertEqual(distringmatch("III"), [0, 1, 2, 3], 'example 2')
+
+  def test_ex3(self):
+    self.assertEqual(distringmatch("DDI"), [3, 2, 0, 1], 'example 3')
+
+unittest.main()
diff --git a/challenge-249/roger-bell-west/raku/ch-1.p6 b/challenge-249/roger-bell-west/raku/ch-1.p6
new file mode 100755
index 0000000000..9f5bdbf702
--- /dev/null
+++ b/challenge-249/roger-bell-west/raku/ch-1.p6
@@ -0,0 +1,23 @@
+#! /usr/bin/raku
+
+use Test;
+
+plan 2;
+
+is-deeply(shortestdistance([3, 2, 3, 2, 2, 2]), [[2, 2], [2, 2], [3, 3]], 'example 1');
+is-deeply(shortestdistance([1, 2, 3, 4]), [], 'example 2');
+
+sub shortestdistance(@a0) {
+    if (@a0.elems % 2 != 0) {
+        return [];
+    }
+    my @a = @a0.sort({$^a <=> $^b});
+    my @out;
+    for @a -> $i, $j {
+        if ($i != $j) {
+            return [];