RogerBW solutions for challenge no. 344

13 files changed, 929 insertions, 0 deletions

diff --git a/challenge-344/roger-bell-west/crystal/ch-1.cr b/challenge-344/roger-bell-west/crystal/ch-1.cr
new file mode 100755
index 0000000000..d9a2169c1e
--- /dev/null
+++ b/challenge-344/roger-bell-west/crystal/ch-1.cr
@@ -0,0 +1,47 @@
+#! /usr/bin/crystal
+
+def u2a(a)
+  p = a
+  if p > 0
+    out = Array(Int32).new
+    while p > 0
+      p, x = p.divmod(10)
+      out.unshift(x)
+    end
+    out
+  else
+    [0]
+  end
+end
+
+def a2u(a)
+  acc = 0
+  a.each do |d|
+    acc *= 10
+    acc += d
+  end
+  acc
+end
+
+def arrayformcompute(a, b)
+  u2a(a2u(a) + b)
+end
+
+require "spec"
+describe "arrayformcompute" do
+  it "test_ex1" do
+    arrayformcompute([1, 2, 3, 4], 12).should eq [1, 2, 4, 6]
+  end
+  it "test_ex2" do
+    arrayformcompute([2, 7, 4], 181).should eq [4, 5, 5]
+  end
+  it "test_ex3" do
+    arrayformcompute([9, 9, 9], 1).should eq [1, 0, 0, 0]
+  end
+  it "test_ex4" do
+    arrayformcompute([1, 0, 0, 0, 0], 9999).should eq [1, 9, 9, 9, 9]
+  end
+  it "test_ex5" do
+    arrayformcompute([0], 1000).should eq [1, 0, 0, 0]
+  end
+end
diff --git a/challenge-344/roger-bell-west/crystal/ch-2.cr b/challenge-344/roger-bell-west/crystal/ch-2.cr
new file mode 100755
index 0000000000..d72185f893
--- /dev/null
+++ b/challenge-344/roger-bell-west/crystal/ch-2.cr
@@ -0,0 +1,51 @@
+#! /usr/bin/crystal
+
+def arrayformation(src, tgt)
+  stack = Array(Tuple(Array(Int32), Set(Int32))).new
+  stack.push({Array(Int32).new, 0.upto(src.size - 1).to_set})
+  while stack.size > 0
+    c = stack.pop
+    if c[0].size == tgt.size()
+      return true
+    else
+      c[1].each do |candidate|
+        offset = c[0].size
+        nextcandidate = c[1].clone
+        nextcandidate.delete(candidate)
+        valid = true
+        seq = c[0].clone
+        src[candidate].each_with_index do |x, i|
+          if x == tgt[i + offset]
+            seq.push(x)
+          else
+            valid = false
+            break
+          end
+        end
+        if valid
+          stack.push({seq, nextcandidate})
+        end
+      end
+    end
+  end
+  false
+end
+
+require "spec"
+describe "arrayformation" do
+  it "test_ex1" do
+    arrayformation([[2, 3], [1], [4]], [1, 2, 3, 4]).should eq true
+  end
+  it "test_ex2" do
+    arrayformation([[1, 3], [2, 4]], [1, 2, 3, 4]).should eq false
+  end
+  it "test_ex3" do
+    arrayformation([[9, 1], [5, 8], [2]], [5, 8, 2, 9, 1]).should eq true
+  end
+  it "test_ex4" do
+    arrayformation([[1], [3]], [1, 2, 3]).should eq false
+  end
+  it "test_ex5" do
+    arrayformation([[7, 4, 6]], [7, 4, 6]).should eq true
+  end
+end
diff --git a/challenge-344/roger-bell-west/perl/ch-1.pl b/challenge-344/roger-bell-west/perl/ch-1.pl
new file mode 100755
index 0000000000..2940175ff0
--- /dev/null
+++ b/challenge-344/roger-bell-west/perl/ch-1.pl
@@ -0,0 +1,40 @@
+#! /usr/bin/perl
+
+use strict;
+use warnings;
+use experimental 'signatures';
+
+use Test::More tests => 5;
+
+is_deeply(arrayformcompute([1, 2, 3, 4], 12), [1, 2, 4, 6], 'example 1');
+is_deeply(arrayformcompute([2, 7, 4], 181), [4, 5, 5], 'example 2');
+is_deeply(arrayformcompute([9, 9, 9], 1), [1, 0, 0, 0], 'example 3');
+is_deeply(arrayformcompute([1, 0, 0, 0, 0], 9999), [1, 9, 9, 9, 9], 'example 4');
+is_deeply(arrayformcompute([0], 1000), [1, 0, 0, 0], 'example 5');
+
+sub u2a($a) {
+  my $p = $a;
+  if ($p > 0) {
+    my @out;
+    while ($p > 0) {
+      unshift @out, $p % 10;
+      $p = int($p / 10);
+    }
+    \@out;
+  } else {
+    [0];
+  }
+}
+
+sub a2u($a) {
+  my $acc = 0;
+  foreach my $d (@{$a}) {
+    $acc *= 10;
+    $acc += $d;
+  }
+  $acc
+}
+
+sub arrayformcompute($a, $b) {
+  u2a(a2u($a) + $b);
+}
diff --git a/challenge-344/roger-bell-west/perl/ch-2.pl b/challenge-344/roger-bell-west/perl/ch-2.pl
new file mode 100755
index 0000000000..da3eafaa7a
--- /dev/null
+++ b/challenge-344/roger-bell-west/perl/ch-2.pl
@@ -0,0 +1,47 @@
+#! /usr/bin/perl
+
+use strict;
+use warnings;
+use experimental 'signatures';
+
+use Test::More tests => 5;
+
+is(arrayformation([[2, 3], [1], [4]], [1, 2, 3, 4]), 1, 'example 1');
+is(arrayformation([[1, 3], [2, 4]], [1, 2, 3, 4]), 0, 'example 2');
+is(arrayformation([[9, 1], [5, 8], [2]], [5, 8, 2, 9, 1]), 1, 'example 3');
+is(arrayformation([[1], [3]], [1, 2, 3]), 0, 'example 4');
+is(arrayformation([[7, 4, 6]], [7, 4, 6]), 1, 'example 5');
+
+use Storable qw(dclone);
+
+sub arrayformation($src, $tgt) {
+  my @stack;
+  push @stack, [[], {map {$_ => 1} 0 .. $#{$src}}];
+  while (scalar @stack > 0) {
+    my $c = pop @stack;
+    if ($#{$c->[0]} == $#{$tgt}) {
+      return 1;
+    } else {
+      foreach my $candidate (keys %{$c->[1]}) {
+        my $offset = scalar @{$c->[0]};
+        my $nextcandidate = dclone($c->[1]);
+        delete $nextcandidate->{$candidate};
+        my $valid = 1;
+        my $seq = dclone($c->[0]);
+        values @{$src->[$candidate]};
+        while (my ($i, $x) = each @{$src->[$candidate]}) {
+          if ($x == $tgt->[$i + $offset]) {
+            push @{$seq}, $x;
+          } else {
+            $valid = 0;
+            last;
+          }
+        }
+        if ($valid) {
+          push @stack, [$seq, $nextcandidate];
+        }
+      }
+    }
+  }
+  0;
+}
diff --git a/challenge-344/roger-bell-west/postscript/ch-1.ps b/challenge-344/roger-bell-west/postscript/ch-1.ps
new file mode 100644
index 0000000000..72ba0f8e95
--- /dev/null
+++ b/challenge-344/roger-bell-west/postscript/ch-1.ps
@@ -0,0 +1,148 @@
+%!PS
+
+% begin included library code
+% see https://codeberg.org/Firedrake/postscript-libraries/
+/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
+
+/reverse {
+    1 dict begin
+    dup length /l exch def
+    [ exch
+      aload pop
+      2 1 l {
+          -1 roll
+      } for
+    ]
+    end
+} 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
+
+/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
+
+/u2a {
+    dup 0 eq {
+        pop
+        [ 0 ]
+    } {
+        [ exch
+            {
+                dup 0 eq {
+                    pop
+                    exit
+                } if
+                dup 10 mod exch
+                10 idiv
+            } loop
+        ]
+        reverse
+    } ifelse
+} bind def
+
+/a2u {
+    0 exch
+    {
+        exch 10 mul add
+    } forall
+} bind def
+
+/arrayformcompute {
+    exch
+    a2u
+    add
+    u2a
+} bind def
+
+(arrayformcompute) test.start
+[1 2 3 4] 12 arrayformcompute [1 2 4 6] deepeq test
+[2 7 4] 181 arrayformcompute [4 5 5] deepeq test
+[9 9 9] 1 arrayformcompute [1 0 0 0] deepeq test
+[1 0 0 0 0] 9999 arrayformcompute [1 9 9 9 9] deepeq test
+[0] 1000 arrayformcompute [1 0 0 0] deepeq test
+test.end
diff --git a/challenge-344/roger-bell-west/postscript/ch-2.ps b/challenge-344/roger-bell-west/postscript/ch-2.ps
new file mode 100644
index 0000000000..8c4697d680
--- /dev/null
+++ b/challenge-344/roger-bell-west/postscript/ch-2.ps
@@ -0,0 +1,153 @@
+%!PS
+
+% begin included library code
+% see https://codeberg.org/Firedrake/postscript-libraries/
+/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
+
+/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
+
+/apush.right { % [a b] c -> [a b c]
+    exch
+    [ exch aload length 2 add -1 roll ]
+} 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
+
+/apop.right { % [a b c] -> [a b] c
+    [ exch aload length 1 add 1 roll ] exch
+} bind def
+
+/keys { % dict -> array of dict keys
+    [ exch
+      {
+          pop
+      } forall
+    ]
+} bind def
+
+/toset { % array -> dict of (value, true)
+    << exch
+       {
+           true
+       } forall
+    >>
+} 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
+
+/arrayformation {
+    0 dict begin
+    /tgt exch def
+    /src exch def
+    /stack [ [ 0 array [ 0 1 src length 1 sub { } for ] toset ] ] def
+    /sol false def
+    {
+        stack length 0 eq {
+            exit
+        } if
+        stack apop.right /c exch def /stack exch def
+        c 0 get length tgt length eq {
+            /sol true def
+            /c 0 array def
+        } {
+            c 1 get keys {
+                /candidate exch def
+                /offset c 0 get length def
+                /nextcandidate c 1 get deepcopy def
+                nextcandidate candidate undef
+                /valid true def
+                /seq c 0 get deepcopy def
+                src candidate get enumerate.array {
+                    aload pop
+                    /x exch def
+                    /i exch def
+                    x tgt i offset add get eq {
+                        /seq seq x apush.right def
+                    } {
+                        /valid false def
+                        exit
+                    } ifelse
+                } forall
+                valid {
+                    /stack stack [ seq nextcandidate ] apush.right def
+                } if
+            } forall
+        } ifelse
+    } loop
+    sol
+    end
+} bind def
+
+(arrayformation) test.start
+[[2 3] [1] [4]] [1 2 3 4] arrayformation test
+[[1 3] [2 4]] [1 2 3 4] arrayformation not test
+[[9 1] [5 8] [2]] [5 8 2 9 1] arrayformation test
+[[1] [3]] [1 2 3] arrayformation not test
+[[7 4 6]] [7 4 6] arrayformation test
+test.end
diff --git a/challenge-344/roger-bell-west/ruby/ch-1.rb b/challenge-344/roger-bell-west/ruby/ch-1.rb
new file mode 100755
index 0000000000..c4e02b9fc3
--- /dev/null
+++ b/challenge-344/roger-bell-west/ruby/ch-1.rb
@@ -0,0 +1,54 @@
+#! /usr/bin/ruby
+
+def u2a(a)
+  p = a
+  if p > 0
+    out = []
+    while p > 0
+      (p, x) = p.divmod(10)
+      out.unshift(x)
+    end
+    out
+  else
+    [0]
+  end
+end
+
+def a2u(a)
+  acc = 0
+  a.each do |d|
+    acc *= 10
+    acc += d
+  end
+  acc
+end
+
+def arrayformcompute(a, b)
+  u2a(a2u(a) + b)
+end
+
+require 'test/unit'
+
+class TestArrayformcompute < Test::Unit::TestCase
+
+  def test_ex1
+    assert_equal([1, 2, 4, 6], arrayformcompute([1, 2, 3, 4], 12))
+  end
+
+  def test_ex2
+    assert_equal([4, 5, 5], arrayformcompute([2, 7, 4], 181))
+  end
+
+  def test_ex3
+    assert_equal([1, 0, 0, 0], arrayformcompute([9, 9, 9], 1))
+  end
+
+  def test_ex4
+    assert_equal([1, 9, 9, 9, 9], arrayformcompute([1, 0, 0, 0, 0], 9999))
+  end
+
+  def test_ex5
+    assert_equal([1, 0, 0, 0], arrayformcompute([0], 1000))
+  end
+
+end
diff --git a/challenge-344/roger-bell-west/ruby/ch-2.rb b/challenge-344/roger-bell-west/ruby/ch-2.rb
new file mode 100755
index 0000000000..20c08bd25c
--- /dev/null
+++ b/challenge-344/roger-bell-west/ruby/ch-2.rb
@@ -0,0 +1,60 @@
+#! /usr/bin/ruby
+
+require 'set'
+
+def arrayformation(src, tgt)
+  stack = []
+  stack.push([[], 0.upto(src.length - 1).to_set])
+  while stack.length > 0
+    c = stack.pop
+    if c[0].length == tgt.length()
+      return true
+    else
+      c[1].each do |candidate|
+        offset = c[0].length
+        nextcandidate = c[1].clone
+        nextcandidate.delete(candidate)
+        valid = true
+        seq = c[0].clone
+        src[candidate].each_with_index do |x, i|
+          if x == tgt[i + offset]
+            seq.push(x)
+          else
+            valid = false
+            break
+          end
+        end
+        if valid
+          stack.push([seq, nextcandidate])
+        end
+      end
+    end
+  end
+  false
+end
+
+require 'test/unit'
+
+class TestArrayformation < Test::Unit::TestCase
+
+  def test_ex1
+    assert_equal(true, arrayformation([[2, 3], [1], [4]], [1, 2, 3, 4]))
+  end
+
+  def test_ex2
+    assert_equal(false, arrayformation([[1, 3], [2, 4]], [1, 2, 3, 4]))
+  end
+
+  def test_ex3
+    assert_equal(true, arrayformation([[9, 1], [5, 8], [2]], [5, 8, 2, 9, 1]))
+  end
+
+  def test_ex4
+    assert_equal(false, arrayformation([[1], [3]], [1, 2, 3]))
+  end
+
+  def test_ex5
+    assert_equal(true, arrayformation([[7, 4, 6]], [7, 4, 6]))
+  end
+
+end
diff --git a/challenge-344/roger-bell-west/rust/ch-1.rs b/challenge-344/roger-bell-west/rust/ch-1.rs
new file mode 100755
index 0000000000..e42f5a8755
--- /dev/null
+++ b/challenge-344/roger-bell-west/rust/ch-1.rs
@@ -0,0 +1,58 @@
+#! /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!(arrayformcompute(vec![1, 2, 3, 4], 12), vec![1, 2, 4, 6]);
+}
+
+#[test]
+fn test_ex2() {
+    assert_eq!(arrayformcompute(vec![2, 7, 4], 181), vec![4, 5, 5]);
+}
+
+#[test]
+fn test_ex3() {
+    assert_eq!(arrayformcompute(vec![9, 9, 9], 1), vec![1, 0, 0, 0]);
+}
+
+#[test]
+fn test_ex4() {
+    assert_eq!(
+        arrayformcompute(vec![1, 0, 0, 0, 0], 9999),
+        vec![1, 9, 9, 9, 9]
+    );
+}
+
+#[test]
+fn test_ex5() {
+    assert_eq!(arrayformcompute(vec![0], 1000), vec![1, 0, 0, 0]);
+}
+
+fn u2a(a: u32) -> Vec<u32> {
+    let mut p = a;
+    if p > 0 {
+        let mut out = Vec::new();
+        while p > 0 {
+            out.push(p % 10);
+            p /= 10;
+        }
+        out.reverse();
+        out
+    } else {
+        vec![0]
+    }
+}
+
+fn a2u(a: Vec<u32>) -> u32 {
+    let mut acc = 0;
+    for d in a {
+        acc *= 10;
+        acc += d;
+    }
+    acc
+}
+
+fn arrayformcompute(a: Vec<u32>, b: u32) -> Vec<u32> {
+    u2a(a2u(a) + b)
+}
diff --git a/challenge-344/roger-bell-west/rust/ch-2.rs b/challenge-344/roger-bell-west/rust/ch-2.rs
new file mode 100755
index 0000000000..372c529573
--- /dev/null
+++ b/challenge-344/roger-bell-west/rust/ch-2.rs
@@ -0,0 +1,74 @@
+#! /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!(
+        arrayformation(vec![vec![2, 3], vec![1], vec![4]], vec![1, 2, 3, 4]),
+        true
+    );
+}
+
+#[test]
+fn test_ex2() {
+    assert_eq!(
+        arrayformation(vec![vec![1, 3], vec![2, 4]], vec![1, 2, 3, 4]),
+        false
+    );
+}
+
+#[test]
+fn test_ex3() {
+    assert_eq!(
+        arrayformation(
+            vec![vec![9, 1], vec![5, 8], vec![2]],
+            vec![5, 8, 2, 9, 1]
+        ),
+        true
+    );
+}
+
+#[test]
+fn test_ex4() {
+    assert_eq!(arrayformation(vec![vec![1], vec![3]], vec![1, 2, 3]), false);
+}
+
+#[test]
+fn test_ex5() {
+    assert_eq!(arrayformation(vec![vec![7, 4, 6]], vec![7, 4, 6]), true);
+}
+
+use std::collections::HashSet;
+
+fn arrayformation(src: Vec<Vec<i32>>, tgt: Vec<i32>) -> bool {
+    let mut stack: Vec<(Vec<i32>, HashSet<usize>)> = Vec::new();
+    stack.push((
+        Vec::new(),
+        (0..src.len()).into_iter().collect::<HashSet<usize>>(),
+    ));
+    while let Some(c) = stack.pop() {
+        if c.0.len() == tgt.len() {
+            return true;
+        } else {
+            for candidate in &c.1 {
+                let offset = c.0.len();
+                let mut nextcandidate = c.1.clone();
+                nextcandidate.remove(&candidate);
+                let mut valid = true;
+                let mut seq = c.0.clone();
+                for (i, x) in src[*candidate].iter().enumerate() {
+                    if *x == tgt[i + offset] {
+                        seq.push(*x);
+                    } else {
+                        valid = false;
+                        break;
+                    }
+                }
+                if valid {
+                    stack.push((seq, nextcandidate));
+                }
+            }
+        }
+    }
+    false
+}
diff --git a/challenge-344/roger-bell-west/tests.json b/challenge-344/roger-bell-west/tests.json
new file mode 100644
index 0000000000..5f81c249ac
--- /dev/null
+++ b/challenge-344/roger-bell-west/tests.json
@@ -0,0 +1,88 @@
+{
+    "ch-1" : [
+        {
+            "function" : "arrayformcompute",
+            "multiarg" : true,
+            "arguments" : [
+                [ 1, 2, 3, 4 ],
+                12
+            ],
+            "result" : [ 1, 2, 4, 6 ]
+        },
+        {
+            "multiarg" : true,
+            "arguments" : [
+                [ 2, 7, 4 ],
+                181
+            ],
+            "result" : [ 4, 5, 5 ]
+        },
+        {
+            "multiarg" : true,
+            "arguments" : [
+                [ 9, 9, 9 ],
+                1
+            ],
+            "result" : [ 1, 0, 0, 0 ]
+        },
+        {
+            "multiarg" : true,
+            "arguments" : [
+                [ 1, 0, 0, 0, 0 ],
+                9999
+            ],
+            "result" : [ 1, 9, 9, 9, 9 ]
+        },
+        {
+            "multiarg" : true,
+            "arguments" : [
+                [ 0 ],
+                1000
+            ],
+            "result" : [ 1, 0, 0, 0 ]
+        }
+    ],
+    "ch-2" : [
+        {
+            "function" : "arrayformation",
+            "multiarg" : true,
+            "arguments" : [
+                [ [2,3], [1], [4] ],
+                [ 1, 2, 3, 4 ]
+            ],
+            "result" : true
+        },
+        {
+            "multiarg" : true,
+            "arguments" : [
+                [ [1,3], [2,4] ],
+                [ 1, 2, 3, 4 ]
+            ],
+            "result" : false
+        },
+        {
+            "multiarg" : true,
+            "arguments" : [
+                [ [9,1], [5,8], [2] ],
+                [ 5, 8, 2, 9, 1 ]
+            ],
+            "result" : true
+        },
+        {
+            "multiarg" : true,
+            "arguments" : [
+                [ [1], [3] ],
+                [ 1, 2, 3 ]
+            ],
+            "result" : false
+        },
+        {
+            "multiarg" : true,
+            "arguments" : [
+                [ [7, 4, 6] ],
+                [ 7, 4, 6 ]
+            ],
+            "result" : true
+        }
+    ]
+}
diff --git a/challenge-344/roger-bell-west/typst/ch-1.typ b/challenge-344/roger-bell-west/typst/ch-1.typ
new file mode 100644
index 0000000000..a09041fc33
--- /dev/null
+++ b/challenge-344/roger-bell-west/typst/ch-1.typ
@@ -0,0 +1,50 @@
+#let testresult(pass) = {
+  if pass {
+    text(fill: green, "Pass")
+  } else {
+    text(fill: red, "Fail")
+  }
+}
+
+#let u2a(a) = {
+  let p = a
+  if p > 0 {
+    let out = ()
+    while p > 0 {
+      out.push(calc.rem-euclid(p, 10))
+      p = calc.div-euclid(p, 10)
+    }
+    out.rev()
+  } else {
+    (0)
+  }
+}
+
+#let a2u(a) = {
+  let acc = 0
+  for d in a {
+    acc *= 10
+    acc += d
+  }
+  acc
+}
+
+#let arrayformcompute(a, b) = {
+  u2a(a2u(a) + b)
+}
+
+Test 1:
+    #testresult(arrayformcompute((1, 2, 3, 4), 12) == (1, 2, 4, 6))
+
+Test 2:
+    #testresult(arrayformcompute((2, 7, 4), 181) == (4, 5, 5))
+
+Test 3:
+    #testresult(arrayformcompute((9, 9, 9), 1) == (1, 0, 0, 0))
+
+Test 4:
+    #testresult(arrayformcompute((1, 0, 0, 0, 0), 9999) == (1, 9, 9, 9, 9))
+
+Test 5:
+    #testresult(arrayformcompute((0, ), 1000) == (1, 0, 0, 0))
+
diff --git a/challenge-344/roger-bell-west/typst/ch-2.typ b/challenge-344/roger-bell-west/typst/ch-2.typ
new file mode 100644
index 0000000000..7f17d7a0f3
--- /dev/null
+++ b/challenge-344/roger-bell-west/typst/ch-2.typ
@@ -0,0 +1,59 @@
+#let testresult(pass) = {
+  if pass {
+    text(fill: green, "Pass")
+  } else {
+    text(fill: red, "Fail")
+  }
+}
+
+#let arrayformation(src, tgt) = {
+  let stack = ()
+  let d = (:)
+  for n in range(src.len()) {
+    d.insert(str(n), true)
+  }
+  stack.push(((), d))
+  let ret = false
+  while stack.len() > 0 {
+    let c = stack.pop()
+    if c.at(0).len() == tgt.len() {
+      ret = true
+      stack = ()
+    } else {
+      for candidate in c.at(1).keys() {
+        let offset = c.at(0).len()
+        let nextcandidate = c.at(1).keys().filter(x => x != candidate).map(x => (x, true)).to-dict()
+        let valid = true
+        let seq = c.at(0).map(x => x)
+        for (i, x) in src.at(int(candidate)).enumerate() {
+          if x == tgt.at(i + offset) {
+            seq.push(x)
+          } else {
+            valid = false
+            break
+          }
+        }
+        if valid {
+          stack.push((seq, nextcandidate))
+        }
+      }
+    }
+  }
+  ret
+}
+
+Test 1:
+    #testresult(arrayformation(((2, 3), (1, ), (4, )), (1, 2, 3, 4)))
+
+Test 2:
+    #testresult(not arrayformation(((1, 3), (2, 4)), (1, 2, 3, 4)))
+
+Test 3:
+    #testresult(arrayformation(((9, 1), (5, 8), (2, )), (5, 8, 2, 9, 1)))
+
+Test 4:
+    #testresult(not arrayformation(((1, ), (3, )), (1, 2, 3)))
+
+Test 5:
+    #testresult(arrayformation(((7, 4, 6), ), (7, 4, 6)))
+