Merge pull request #5629 from Abigail/abigail/week-151

Abigail/week 151

25 files changed, 708 insertions, 26 deletions

diff --git a/challenge-151/abigail/README.md b/challenge-151/abigail/README.md
index 352bb54018..870c6804c1 100644
--- a/challenge-151/abigail/README.md
+++ b/challenge-151/abigail/README.md
@@ -4,50 +4,24 @@
 
 * [AWK](awk/ch-1.awk)
 * [Bash](bash/ch-1.sh)
-* [Bc](bc/ch-1.bc)
 * [C](c/ch-1.c)
-* [Go](go/ch-1.go)
-* [Java](java/ch-1.java)
 * [Lua](lua/ch-1.lua)
 * [Node.js](node/ch-1.js)
-* [Pascal](pascal/ch-1.p)
 * [Perl](perl/ch-1.pl)
 * [Python](python/ch-1.py)
-* [R](r/ch-1.r)
 * [Ruby](ruby/ch-1.rb)
-* [Scheme](scheme/ch-1.scm)
-* [Tcl](tcl/ch-1.tcl)
 
 
 ## Part 2
 
 * [AWK](awk/ch-2.awk)
 * [Bash](bash/ch-2.sh)
-* [Basic](basic/ch-2.bas)
-* [Bc](bc/ch-2.bc)
-* [Befunge-93](befunge-93/ch-2.bf93)
 * [C](c/ch-2.c)
-* [Cobol](cobol/ch-2.cb)
-* [Csh](csh/ch-2.csh)
-* [Erlang](lua/ch-2.erl)
-* [Forth](lua/ch-2.fs)
-* [Fortran](fortran/ch-2.f90)
 * [Go](go/ch-2.go)
-* [Java](java/ch-2.java)
 * [Lua](lua/ch-2.lua)
-* [m4](m4/ch-2.m4)
-* [MMIX](mmix/ch-2.mms)
 * [Node.js](node/ch-2.js)
-* [OCaml](ocaml/ch-2.ml)
 * [Pascal](pascal/ch-2.p)
 * [Perl](perl/ch-2.pl)
-* [PHP](php/ch-2.php)
-* [PostScript](postscript/ch-2.ps)
 * [Python](python/ch-2.py)
 * [R](r/ch-2.r)
-* [Rexx](rexx/ch-2.rexx)
 * [Ruby](ruby/ch-2.rb)
-* [Scheme](scheme/ch-2.scm)
-* [Sed](sed/ch-2.sed)
-* [SQL](sql/ch-2.sql)
-* [Tcl](tcl/ch-2.tcl)
diff --git a/challenge-151/abigail/awk/ch-1.awk b/challenge-151/abigail/awk/ch-1.awk
new file mode 100644
index 0000000000..314efa9a0a
--- /dev/null
+++ b/challenge-151/abigail/awk/ch-1.awk
@@ -0,0 +1,42 @@
+#!/usr/bin/awk
+
+#
+# See https://theweeklychallenge.org/blog/perl-weekly-challenge-151
+#
+
+#
+# Run as: awk -f ch-1.awk < input-file
+#
+
+{
+    #
+    # Read in tree
+    #
+    delete tree
+    D = 0
+    i = 0
+    for (k = 0; k < NF; k ++) {
+        if ($k == "|") {
+            D ++
+            i = 0
+        }
+        else {
+            tree [D, i ++] = $k == "*" ? 0 : 1
+        }
+    }
+
+    #
+    # Find first node without children
+    #
+    for (d = 0; d <= D; d ++) {
+        for (i = 0; i < 2 ^ d; i ++) {
+            if (tree [d, i] && !tree [d + 1, 2 * i] && 
+                               !tree [d + 1, 2 * i + 1]) {
+                print d + 1
+                next
+            }
+        }
+    }
+}
+
+
diff --git a/challenge-151/abigail/awk/ch-2.awk b/challenge-151/abigail/awk/ch-2.awk
new file mode 100644
index 0000000000..732444708f
--- /dev/null
+++ b/challenge-151/abigail/awk/ch-2.awk
@@ -0,0 +1,21 @@
+#!/usr/bin/awk
+
+#
+# See https://theweeklychallenge.org/blog/perl-weekly-challenge-151
+#
+
+#
+# Run as: awk -f ch-2.awk < input-file
+#
+
+function max (a, b) {
+    return a < b ? b : a
+}
+
+{
+    for (i = NF; i > 2; i --) {
+        $i = max($i + $(i + 2), $(i + 1))
+    }
+    print $1 + $3
+}
+
diff --git a/challenge-151/abigail/bash/ch-1.sh b/challenge-151/abigail/bash/ch-1.sh
new file mode 100644
index 0000000000..eff4fc05e6
--- /dev/null
+++ b/challenge-151/abigail/bash/ch-1.sh
@@ -0,0 +1,41 @@
+#!/bin/sh
+
+#
+# See https://theweeklychallenge.org/blog/perl-weekly-challenge-151
+#
+
+#
+# Run as: bash ch-1.sh < input-file
+#
+
+set -f
+
+declare -A tree
+
+while read -a tokens
+do    tree=()
+      D=0
+      i=0
+      for token in ${tokens[@]}
+      do  if [ $token == "|" ]
+          then D=$((D + 1))
+               i=0
+          else key=$D,$i
+               if [ $token != "*" ]
+               then tree[$key]=1
+               fi
+               i=$((i + 1))
+          fi
+      done
+
+      for ((d = 0; d <= D; d ++))
+      do  for ((i = 0; i < 2 ** d; i ++))
+          do  if [[   -v tree[$d,$i]                      ]] && \
+                 [[ ! -v tree[$((d + 1)),$((2 * $i))]     ]] && \
+                 [[ ! -v tree[$((d + 1)),$((2 * $i + 1))] ]]
+              then echo $((d + 1))
+                   break 2
+              fi
+          done
+      done
+done
diff --git a/challenge-151/abigail/bash/ch-2.sh b/challenge-151/abigail/bash/ch-2.sh
new file mode 100644
index 0000000000..cb009e0e16
--- /dev/null
+++ b/challenge-151/abigail/bash/ch-2.sh
@@ -0,0 +1,23 @@
+#!/bin/sh
+
+#
+# See https://theweeklychallenge.org/blog/perl-weekly-challenge-151
+#
+
+#
+# Run as: bash ch-2.sh < input-file
+#
+
+set -f
+
+while read -a h
+do    h[${#h[@]}]=0
+      h[${#h[@]}]=0
+      for  ((i = ${#h[@]} - 3; i >= 2; i --))
+      do   ((val1 = ${h[$i]} + ${h[$((i + 2))]}))
+           ((val2 = ${h[$((i + 1))]}))
+           h[$i]=$((val1 < val2 ? val2 : val1))
+      done
+
+      echo $((${h[0]} + ${h[2]}))
+done
diff --git a/challenge-151/abigail/c/ch-1.c b/challenge-151/abigail/c/ch-1.c
new file mode 100644
index 0000000000..e4487ddaec
--- /dev/null
+++ b/challenge-151/abigail/c/ch-1.c
@@ -0,0 +1,96 @@
+# include <stdlib.h>
+# include <stdio.h>
+# include <string.h>
+# include <stdbool.h>
+# include <ctype.h>
+
+/*
+ * See https://theweeklychallenge.org/blog/perl-weekly-challenge-151
+ */
+
+/*
+ * Run as: cc -o ch-1.o ch-1.c; ./ch-1.o < input-file
+ */
+
+int main (void) {
+    char *  line    = NULL;
+    size_t  len     = 0;
+    size_t  str_len;
+
+    while ((str_len = getline (&line, &len, stdin)) != -1) {
+        char * line_ptr = line;
+        /*
+         * Count the number of '|' characters; this determines
+         * how many elements to allocate for our tree.
+         */
+        int size = 3;
+        while (* line_ptr) {
+            if (* line_ptr ++ == '|') {
+                size = 2 * size + 1;
+            }
+        }
+        bool * tree;
+        if ((tree = (bool *) malloc (size * sizeof (bool))) == NULL) {
+            perror ("Malloc tree failed");
+            exit (1);
+        }
+        for (size_t i = 0; i < size; i ++) {
+            tree [i] = false;
+        }
+
+        int D = 0;
+        int i = 0;
+        size_t offset = 0;
+        line_ptr = line;
+        /*
+         * Skip leading spaces
+         */
+        while (* line_ptr && isspace (* line_ptr)) {
+            line_ptr ++;
+        }
+        while (* line_ptr) {
+            if (* line_ptr == '|') {
+                D ++;
+                i = 0;
+                offset = 2 * offset + 1;
+                line_ptr ++;
+                continue;
+            }
+            if (* line_ptr == '*') {
+                i ++;
+                line_ptr ++;
+                continue;
+            }
+            if (isspace (* line_ptr)) {
+                while (* line_ptr && isspace (* line_ptr)) {
+                    line_ptr ++;
+                }
+                continue;
+            }
+            tree [offset + i] = true;
+            i ++;
+            while (* line_ptr && !isspace (* line_ptr) && * line_ptr != '|') {
+                line_ptr ++;
+            }
+        }
+
+        int width = 1;
+        int k     = 0;
+        bool done = false;
+        for (int d = 0; d <= D && !done; d ++) {
+            for (int i = 0; i < width && !done; i ++) {
+                if (tree [k] && !tree [2 * k + 1] && !tree [2 * k + 2]) {
+                    printf ("%d\n", d + 1);
+                    done = true;
+                }
+                k ++;
+            }
+            width *= 2;
+        }
+
+        free (tree);
+    }
+    free (line);
+
+    return (0);
+}
diff --git a/challenge-151/abigail/c/ch-2.c b/challenge-151/abigail/c/ch-2.c
new file mode 100644
index 0000000000..9c46968f80
--- /dev/null
+++ b/challenge-151/abigail/c/ch-2.c
@@ -0,0 +1,52 @@
+# include <stdlib.h>
+# include <stdio.h>
+# include <string.h>
+
+/*
+ * See https://theweeklychallenge.org/blog/perl-weekly-challenge-151
+ */
+
+/*
+ * Run as: cc -o ch-2.o ch-2.c; ./ch-2.o < input-file
+ */
+
+int max (int a, int b) {
+    return a < b ? b : a;
+}
+
+int main (void) {
+    char *  line    = NULL;
+    size_t  len     = 0;
+    size_t  str_len;
+
+    while ((str_len = getline (&line, &len, stdin)) != -1) {
+        char * line_ptr = line;
+        int * h = NULL;
+        int val;
+        int offset;
+        int sz = 0;
+
+        while (sscanf (line_ptr, "%d%n", &val, &offset) == 1) {
+            if ((h = (int *) realloc (h, (2 + ++ sz) * sizeof (int))) == NULL) {
+                perror ("Recalloc failed");
+                exit (1);
+            }
+            h [sz - 1] = val;
+            line_ptr += offset;
+        }
+
+        h [sz + 0] = 0;
+        h [sz + 1] = 0;
+
+        for (int i = sz - 1; i >= 2; i --) {
+            h [i] = max (h [i] + h [i + 2], h [i + 1]);
+        }
+
+        printf ("%d\n", h [0] + h [2]);
+
+        free (h);
+    }
+    free (line);
+
+    return (0);
+}
diff --git a/challenge-151/abigail/go/ch-2.go b/challenge-151/abigail/go/ch-2.go
new file mode 100644
index 0000000000..a8b6725ffa
--- /dev/null
+++ b/challenge-151/abigail/go/ch-2.go
@@ -0,0 +1,48 @@
+package main
+
+//
+// See https://theweeklychallenge.org/blog/perl-weekly-challenge-151
+//
+
+//
+// Run as: go run ch-2.go < input-file
+//
+
+import (
+    "fmt"
+    "bufio"
+    "os"
+    "strconv"
+    "strings"
+)
+
+func max (a int, b int) int {
+    if a < b {
+        return b
+    }
+    return a
+}
+
+func main () {
+    var reader = bufio . NewReader (os. Stdin)
+    for {
+        var text, err = reader . ReadString ('\n')
+        if (err != nil) {
+            break
+        }
+
+        s := strings . Fields (strings . Trim (text, "\n"))
+        h := make ([] int, len (s))
+        for i, v := range s {
+            n, _ := strconv . Atoi (v)
+            h [i] = n
+        }
+        h = append (h, 0, 0)
+
+        for i := len (h) - 3; i >= 2; i -- {
+            h [i] = max (h [i] + h [i + 2], h [i + 1])
+        }
+
+        fmt . Println (h [0] + h [2])
+    }
+}
diff --git a/challenge-151/abigail/lua/ch-1.lua b/challenge-151/abigail/lua/ch-1.lua
new file mode 100644
index 0000000000..1d8664060f
--- /dev/null
+++ b/challenge-151/abigail/lua/ch-1.lua
@@ -0,0 +1,45 @@
+#!/opt/local/bin/lua
+
+--
+-- See https://theweeklychallenge.org/blog/perl-weekly-challenge-151
+--
+
+--
+-- Run as: lua ch-1.lua < input-file
+--
+
+for line in io . lines () do
+    local tree = {}
+    local d = 1
+    local i = 1
+    tree [d] = {}
+    for token in line : gmatch ("(%S+)") do
+        if token == "|" then
+            d = d + 1
+            i = 1
+            tree [d] = {}
+            goto end_loop
+        end
+        if token == "*" then
+            i = i + 1
+            goto end_loop
+        end
+
+        tree [d] [i] = 1
+        i = i + 1
+
+        ::end_loop::
+    end
+
+    for d, row in ipairs (tree) do
+        for i, _ in pairs (row) do
+            if not tree [d + 1] or
+               not tree [d + 1] [2 * i - 1] and not tree [d + 1] [2 * i] then
+                print (d)
+                goto end_main
+            end
+        end
+    end
+
+    ::end_main::
+end
diff --git a/challenge-151/abigail/lua/ch-2.lua b/challenge-151/abigail/lua/ch-2.lua
new file mode 100644
index 0000000000..d8ac15c101
--- /dev/null
+++ b/challenge-151/abigail/lua/ch-2.lua
@@ -0,0 +1,25 @@
+#!/opt/local/bin/lua
+
+--
+-- See https://theweeklychallenge.org/blog/perl-weekly-challenge-151
+--
+
+--
+-- Run as: lua ch-2.lua < input-file
+--
+
+for line in io . lines () do
+    local h = {}
+    for val in line : gmatch ("%d+") do
+        h [#h + 1] = val
+    end
+
+    h [#h + 1] = 0
+    h [#h + 1] = 0
+
+    for i = #h - 2, 3, -1 do
+        h [i] = math . max (h [i] + h [i + 2], h [i + 1])
+    end
+
+    print (h [1] + h [3])
+end
diff --git a/challenge-151/abigail/node/ch-1.js b/challenge-151/abigail/node/ch-1.js
new file mode 100644
index 0000000000..bf67eda21e
--- /dev/null
+++ b/challenge-151/abigail/node/ch-1.js
@@ -0,0 +1,33 @@
+#!/usr/local/bin/node
+
+//
+// See https://theweeklychallenge.org/blog/perl-weekly-challenge-151
+//
+
+//
+// Run as: node ch-1.js < input-file
+//
+
+  require ('readline')
+. createInterface ({input: process . stdin})   
+. on              ('line', line => {
+    let tree = line . split ("\|") . map (row => row . trim () . split (/ +/))
+
+    for (let d = 0; d < tree . length; d ++) {
+        if (d == tree . length - 1) {
+            return
+        }
+        let c_row = tree [d]
+        let n_row = tree [d + 1]
+        for (let i = 0; i < c_row . length; i ++) {
+            let ch1 = 2 * i
+            let ch2 = 2 * i + 1
+            if (c_row [i] != "*"                                   &&
+                     (ch1 >= n_row . length || n_row [ch1] == "*") &&
+                     (ch2 >= n_row . length || n_row [ch2] == "*")) {
+                console . log (d + 1)
+                return;
+            }
+        }
+    }
+})
diff --git a/challenge-151/abigail/node/ch-2.js b/challenge-151/abigail/node/ch-2.js
new file mode 100644
index 0000000000..11a88c6bc7
--- /dev/null
+++ b/challenge-151/abigail/node/ch-2.js
@@ -0,0 +1,21 @@
+#!/usr/local/bin/node
+
+//
+// See https://theweeklychallenge.org/blog/perl-weekly-challenge-151
+//
+
+//
+// Run as: node ch-2.js < input-file
+//
+
+  require ('readline')
+. createInterface ({input: process . stdin})   
+. on              ('line', line => {
+    let h = line . trim () . split (/ +/) . map (n => +n)
+    h [h . length] = 0
+    h [h . length] = 0
+    for (let i = h . length - 3; i >= 2; i --) {
+        h [i] = Math . max (h [i] + h [i + 2], h [i + 1])
+    }
+    console . log (h [0] + h [2])
+})
diff --git a/challenge-151/abigail/pascal/ch-2.p b/challenge-151/abigail/pascal/ch-2.p
new file mode 100644
index 0000000000..18053673e2
--- /dev/null
+++ b/challenge-151/abigail/pascal/ch-2.p
@@ -0,0 +1,41 @@
+Program ch2;
+
+(*                                                                   *)
+(* See https://theweeklychallenge.org/blog/perl-weekly-challenge-151 *)
+(*                                                                   *)
+
+(*                                                        *)
+(* Run as: fpc -och-2.out ch-2.p; ./ch-2.out < input-file *)
+(*                                                        *)
+
+uses
+    math;
+
+var
+    h: array of integer;
+    i, sz: integer;
+
+begin
+    while not eof do begin
+        sz := 0;
+        setlength (h, sz);
+
+        while not eoln do begin
+            inc (sz);
+            setlength (h, sz);
+            read (h [sz - 1]);
+        end;
+
+        setlength (h, sz + 2);
+        h [sz + 0] := 0;
+        h [sz + 1] := 0;
+
+        for i := sz - 1 downto 2 do begin
+            h [i] := max (h [i] + h [i + 2], h [i + 1]);
+        end;
+
+        writeln (h [0] + h [2]);
+
+        readln;
+    end
+end.
diff --git a/challenge-151/abigail/perl/ch-1.pl b/challenge-151/abigail/perl/ch-1.pl
new file mode 100644
index 0000000000..73296d77c3
--- /dev/null
+++ b/challenge-151/abigail/perl/ch-1.pl
@@ -0,0 +1,39 @@
+#!/opt/perl/bin/perl
+
+use 5.032;
+
+use strict;
+use warnings;
+no  warnings 'syntax';
+
+use experimental 'signatures';
+use experimental 'lexical_subs';
+
+#
+# See https://theweeklychallenge.org/blog/perl-weekly-challenge-151
+#
+
+#
+# Run as: perl ch-1.pl < input-file
+#
+
+#
+# We'll store the tree in a triangular 2-d array, with
+# the children on node on position [$d, $k] on positions
+# [$d + 1, 2 * $k] and [$d + 1, 2 * $k + 1].
+#
+# Finding the first node without children is trivial.
+#
+TREE: while (<>) {
+    chomp;
+    my @tree = map {[map {$_ ne '*'} /\S+/g]} split /\|/;
+    foreach my $d (keys @tree) {
+        foreach my $i (keys @{$tree [$d]}) {
+            if ($tree [$d] [$i] && !$tree [$d + 1] [2 * $i]
+                                && !$tree [$d + 1] [2 * $i + 1]) {
+                say $d + 1;
+                next TREE;
+            }
+        }
+    }
+}
diff --git a/challenge-151/abigail/perl/ch-2.pl b/challenge-151/abigail/perl/ch-2.pl
new file mode 100644
index 0000000000..df731f4cfe
--- /dev/null
+++ b/challenge-151/abigail/perl/ch-2.pl
@@ -0,0 +1,43 @@
+#!/opt/perl/bin/perl
+
+use 5.032;
+
+use strict;
+use warnings;
+no  warnings 'syntax';
+
+use experimental 'signatures';
+use experimental 'lexical_subs';
+
+#
+# See https://theweeklychallenge.org/blog/perl-weekly-challenge-151
+#
+
+#
+# Run as: perl ch-2.pl < input-file
+#
+
+use List::Util qw [max];
+
+#
+# We'll calculate the best way to rob the houses by working backwards.
+# For each house, there are two options: rob the house, or skip it.
+# The maximum value we get for robbing the house is the sum of
+# the value of the current house, plus the maximum we can get
+# if we started two houses down. The maximum value we can get by
+# not robbing this house is the best we can get by starting from
+# the next house. We'll add two empty houses to make everything work
+# out nicely.
+#
+# Note that we don't have to calculate the best option starting
+# from the second house, as we will always skip the second house.
+# And we must always pick the first house.
+#
+
+while (<>) {
+    my @h = (/[0-9]+/g, 0, 0);
+    $h [$_] = max $h [$_] + $h [$_ + 2], $h [$_ + 1] for reverse 2 .. $#h - 2;
+    say $h [0] + $h [2];
+}
+
+__END__
diff --git a/challenge-151/abigail/python/ch-1.py b/challenge-151/abigail/python/ch-1.py
new file mode 100644
index 0000000000..12dec88d86
--- /dev/null
+++ b/challenge-151/abigail/python/ch-1.py
@@ -0,0 +1,32 @@
+#!/usr/local/bin/python3
+
+#
+# See https://theweeklychallenge.org/blog/perl-weekly-challenge-151
+#
+
+#
+# Run as: python ch-1.py < input-file
+#
+
+import fileinput
+
+for line in fileinput . input ():
+    tree = list (map (lambda row: row . strip () . split (),
+                                 line . strip () . split ("|")))
+    for d in range (len (tree)):
+        if (d == len (tree) - 1):
+            print (d + 1)
+            break
+        done = False
+        for i in range (len (tree [d])):
+            if tree [d] [i] != "*":
+                ch1 = 2 * i
+                ch2 = 2 * i + 1
+                if ch1 >= len (tree [d + 1]) or (
+                    (tree [d + 1] [ch1] == "*" and (
+                      ch2 >= len (tree [d + 1]) or tree [d + 1] [ch2] == "*"))):
+                    print (d + 1)
+                    done = True
+                    break
+        if done:
+            break
diff --git a/challenge-151/abigail/python/ch-2.py b/challenge-151/abigail/python/ch-2.py
new file mode 100644
index 0000000000..52522eff0b
--- /dev/null
+++ b/challenge-151/abigail/python/ch-2.py
@@ -0,0 +1,19 @@
+#!/usr/local/bin/python3
+
+#
+# See https://theweeklychallenge.org/blog/perl-weekly-challenge-151
+#
+
+#
+# Run as: python ch-2.py < input-file
+#
+
+import fileinput
+
+for line in fileinput . input ():
+    h = list (map (lambda x: int (x), line . strip () . split ()))
+    h . append (0)
+    h . append (0)
+    for i in range (len (h) - 3, 1, -1):
+        h [i] = max (h [i] + h [i + 2], h [i + 1])
+    print (h [0] + h [2])
diff --git a/challenge-151/abigail/r/ch-2.r b/challenge-151/abigail/r/ch-2.r
new file mode 100644
index 0000000000..5d2e166d4a
--- /dev/null
+++ b/challenge-151/abigail/r/ch-2.r
@@ -0,0 +1,22 @@
+#!/usr/local/bin/Rscript
+
+#
+# See https://theweeklychallenge.org/blog/perl-weekly-challenge-151
+#
+
+#
+# Run as: Rscript ch-2.r < input-file
+#
+
+stdin <- file ('stdin', 'r')
+repeat {
+    line <- readLines (stdin, n = 1)
+    if (length (line) == 0) {
+        break
+    }
+    h <- c (as.numeric (strsplit (line, " ") [[1]]), 0, 0)
+    for (i in seq (length (h) - 2, 3, -1)) {
+        h [[i]] <- max (c (h [[i]] + h [[i + 2]], h [[i + 1]]))
+    }
+    cat (h [[1]] + h [[3]], "\n")
+}
diff --git a/challenge-151/abigail/ruby/ch-1.rb b/challenge-151/abigail/ruby/ch-1.rb
new file mode 100644
index 0000000000..1164c5bdfc
--- /dev/null
+++ b/challenge-151/abigail/ruby/ch-1.rb
@@ -0,0 +1,31 @@
+#!/usr/bin/ruby
+
+#
+# See https://theweeklychallenge.org/blog/perl-weekly-challenge-151
+#
+ 
+#
+# Run as: ruby ch-1.rb < input-file
+#
+
+ARGF . each_line do |line|
+    tree = line . strip() . split(/\|/) . map do |row|
+        row . strip() . split(/ +/) . map do |x|
+            x == "*" ? false : true
+        end
+    end
+    done = false
+    for d in 0 .. tree . length() - 1 do
+        for i in 0 .. tree [d] . length() - 1 do
+            if tree [d] [i] && !tree [d + 1] [2 * i] &&
+                               !tree [d + 1] [2 * i + 1] then
+                puts (d + 1)
+                done = true
+                break
+            end
+        end
+        if done then
+            break
+        end
+    end
+end
diff --git a/challenge-151/abigail/ruby/ch-2.rb b/challenge-151/abigail/ruby/ch-2.rb
new file mode 100644
index 0000000000..ebdd805af5
--- /dev/null
+++ b/challenge-151/abigail/ruby/ch-2.rb
@@ -0,0 +1,17 @@
+#!/usr/bin/ruby
+
+#
+# See https://theweeklychallenge.org/blog/perl-weekly-challenge-151
+#
+ 
+#
+# Run as: ruby ch-2.rb < input-file
+#
+
+ARGF . each_line do |line|
+    (h = line . split . map do |n| n . to_i end) . push(0, 0)
+    (h . length - 3) . downto(2) do |i|
+        h[i] = [h[i] + h[i + 2], h[i + 1]] . max
+    end
+    puts (h[0] + h[2])
+end
diff --git a/challenge-151/abigail/t/ctest.ini b/challenge-151/abigail/t/ctest.ini
new file mode 100644
index 0000000000..0a8cb97d18
--- /dev/null
+++ b/challenge-151/abigail/t/ctest.ini
@@ -0,0 +1,9 @@
+# 

+# Configuration file for running tests, using ctest.

+# See https://github.com/Abigail/Misc/blob/master/ctest

+# 

+

+[names]

+1-1 = Given Examples

+2-1 = Given Examples

+

diff --git a/challenge-151/abigail/t/input-1-1 b/challenge-151/abigail/t/input-1-1
new file mode 100644
index 0000000000..61fb9ed0dc
--- /dev/null
+++ b/challenge-151/abigail/t/input-1-1
@@ -0,0 +1,2 @@
+1 | 2 3 | 4 5
+1 | 2 3 | 4 *  * 5 | * 6
diff --git a/challenge-151/abigail/t/input-2-1 b/challenge-151/abigail/t/input-2-1
new file mode 100644
index 0000000000..14b0f0f2c6
--- /dev/null
+++ b/challenge-151/abigail/t/input-2-1
@@ -0,0 +1,2 @@
+2 4 5
+4 2 3 6 5 3
diff --git a/challenge-151/abigail/t/output-1-1.exp b/challenge-151/abigail/t/output-1-1.exp
new file mode 100644
index 0000000000..4792e70f33
--- /dev/null
+++ b/challenge-151/abigail/t/output-1-1.exp
@@ -0,0 +1,2 @@
+2
+3
diff --git a/challenge-151/abigail/t/output-2-1.exp b/challenge-151/abigail/t/output-2-1.exp
new file mode 100644
index 0000000000..dd80f6a91d
--- /dev/null
+++ b/challenge-151/abigail/t/output-2-1.exp
@@ -0,0 +1,2 @@
+7
+13