Merge pull request #3913 from Abigail/abigail/week-108

Abigail/week 108

51 files changed, 805 insertions, 136 deletions

diff --git a/challenge-108/abigail/README.md b/challenge-108/abigail/README.md
index 67392c9e54..32dc7d1d9d 100644
--- a/challenge-108/abigail/README.md
+++ b/challenge-108/abigail/README.md
@@ -1,157 +1,70 @@
-# Solution by Abigail
-## [Self-descriptive Numbers](https://perlweeklychallenge.org/blog/perl-weekly-challenge-107/#TASK1)
+# Solutions by Asbigail
+## [Locate Memory](https://perlweeklychallenge.org/blog/perl-weekly-challenge-108/#TASK1)
 
-Write a script to display the first three self-descriptive numbers.
-As per [wikipedia](https://en.wikipedia.org/wiki/Self-descriptive_number),
-the definition of Self-descriptive Number is
-
-> In mathematics, a self-descriptive number is an integer `m` that in a
-> given base `b` is `b` digits long in which each digit `d` at position `n`
-> (the most significant digit being at position 0 and the least
-> significant at position `b - 1`) counts how many instances of
-> digit `n` are in `m`.
-
-### Example
-~~~~
- 1210 is a four-digit self-descriptive number:
-
-    position 0 has value 1 i.e. there is only one 0 in the number
-    position 1 has value 2 i.e. there are two 1 in the number
-    position 2 has value 1 i.e. there is only one 2 in the number
-    position 3 has value 0 i.e. there is no 3 in the number
-~~~~
-
-### Output
-~~~~
-    1210, 2020, 21200
-~~~~
-
-### Notes
-
-This is a trivial exercise -- as all exercises are which do not
-take any input, and which have a fixed output. Fixed output
-challenges are boring -- unless there's another condition (golf,
-for instance).
-
-This exercise is so trivial, we don't even have to head to the OEIS
-to download the wanted numbers, as the expected output is stated
-in the exercise.
-
-So, all we need to do is print three numbers, separated by commas.
-
-The easiest way would be to just do what the challenge demands
-from us, and print the output as given.
-
-A slightly less easy way would be to head over the given
-[Wikipedia page](https://en.wikipedia.org/wiki/Self-descriptive_number)
-(or the [OEIS](https://oeis.org) for that matter), copy the first
-three numbers, and print those out.
-
-But those solutions no doubt will cause scorn in two weeks,
-when the review comes out. It's all "advice about the code is the thing".
-
-But that raises the question, what is the code which is wanted? 
-You could generate all the numbers of length `b` in base `b`, while
-increasing `b`, test them for being self-descriptive, and print 
-the first three numbers found.
-
-My advice about brute force code when there is a more efficient way:
-Don't ever do that.
-
-If we just imagine the Wikipedia page didn't list any self-descriptive
-numbers, and Neil Sloane has forgotten to pay the fee for the OEIS
-domain, so it was taken off-line, then it's still easy to determine
-the first three self-descriptive numbers -- no code required.
-
-Given the following observations for a self-descriptive number `N` in base `b`:
-* `N` has `b` digits, and does not start with a `0`.
-* The sum of the digits of `N` is `b`.
-* No digit of `N` equals `b - 1`.
-* The last digit of `N` is `0`.
-* If `b > 4`, then `N` does not start with a `1`.
-* If `b > 4`, then `N` does not start with `b - 2`.
-
-From that, it's easy to determine that:
-* There are no self-descriptive numbers in any base below `4`.
-* A self-descriptive number in base `4` must start with a `1` or `2`. And
-  end with a `0`. If it starts with a `1`, the middle digits are `1` and `2`.
-  If it starts with a `2`, the middle digits are `0` and `2`. Both `1210`,
-  and `2020"`are self-descriptive numbers.
-* A self-descriptive number in base `5` must start with a `2`, and end
-  with a `0`. The three middle digits must be `0`, `1`, and `2`. `21200`
-  is a self-descriptive number.
-
-(For a more detailed derivation, with all the details filled in, see [the blog
-post](https://abigail.github.io/HTML/Perl-Weekly-Challenge/week-107-1.html))
-
-But this still makes this challenge a glorified `Hello, World!`
-program, as there is no useful code to write to generate the numbers.
+Write a script to declare a variable or constant and print it's
+location in the memory.
 
 ### Solutions
-* [AWK](awk/ch-1.awk)
-* [Bash](bash/ch-1.awk)
-* [BASIC](basic/ch-1.bas)
-* [bc](bc/ch-1.bc)
-* [Befunge-93](befunge-93/ch-1.bf93)
 * [C](c/ch-1.c)
-* [Cobol](cobol/ch-1.cb)
-* [Csh](csh/ch-1.csh)
-* [Erlang](erlang/ch-1.erl)
-* [Forth](forth/ch-1.fs)
-* [Fortran](fortran/ch-1.fs)
+* [Fortran](fortran/ch-1.f90)
 * [Go](go/ch-1.go)
-* [Java](java/ch-1.java)
-* [Lua](lua/ch-1.lua)
-* [m4](m4/ch-1.m4)
-* [Node.js](lua/ch-1.js)
-* [OCaml](ocaml/ch-1.ml)
-* [Pascal](pascal/ch-1.pl)
+* [Pascal](pascal/ch-1.p)
 * [Perl](perl/ch-1.pl)
-* [PHP](php/ch-1.pl)
-* [PostScript](postscript/ch-1.ps)
 * [Python](python/ch-1.py)
 * [R](r/ch-1.r)
-* [Rexx](rexx/ch-1.rexx)
 * [Ruby](ruby/ch-1.rb)
-* [Scheme](scheme/ch-1.scm)
-* [sed](sed/ch-1.sed)
-* [SQL](sql/ch-1.sql)
-* [Tcl](tcl/ch-1.tcl)
 
 ### Blog
-[Perl Weekly Challenge 107: Self-descriptive Numbers](https://abigail.github.io/HTML/Perl-Weekly-Challenge/week-107-1.html)
-
-## [List Methods](https://perlweeklychallenge.org/blog/perl-weekly-challenge-107/#TASK2)
+[Locate Memory](https://abigail.github.io/HTML/Perl-Weekly-Challenge/week-108-1.html)
 
-Write a script to list methods of a package/class.
 
-### Example
-Given the package:
-~~~~
-package Calc;
+## [Bell Numbers](https://perlweeklychallenge.org/blog/perl-weekly-challenge-108/#TASK2)
 
-use strict;
-use warnings;
+Write a script to display top 10 Bell Numbers. Please refer to
+[wikipedia page](https://en.wikipedia.org/wiki/Bell_number) for
+more informations.
 
-sub new { bless {}, shift; }
-sub add { }
-sub mul { }
-sub div { }
-
-1;
-~~~~
-Output:
-~~~~
-BEGIN
-mul
-div
-new
-add
-~~~~
+### Example
+* `B_0 = 1`, as you can only have one partition of zero element set
+* `B_1 = 1`, as you can only have one partition of one element set {a}.
+* `B_2 = 2`, `{a}{b}`, `{a,b}`.
+* `B_3 = 5`, `{a}{b}{c}`, `{a,b}{c}`, `{a}{b,c}`, `{a,c}{b}`, `{a,b,c}`.
+* `B_4 = 15`, `{a}{b}{c}{d}`, `{a,b,c,d}`, `{a,b}{c,d}`, `{a,c}{b,d}`,
+              `{a,d}{b,c}`, `{a,b}{c}{d}`, `{a,c}{b}{d}`, `{a,d}{b}{c}`,
+              `{b,c}{a}{d}`, `{b,d}{a}{c}`, `{c,d}{a}{b}`, `{a}{b,c,d}`,
+              `{b}{a,c,d}`, `{c}{a,b,d}`, `{d}{a,b,c}`
 
 ### Solutions
+* [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](erlang/ch-2.erl)
+* [Forth](forth/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)
+* [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)
 
 ### Blog
-[Perl Weekly Challenge 107: List Methods](https://abigail.github.io/HTML/Perl-Weekly-Challenge/week-107-2.html)
+[Bell Numbers](https://abigail.github.io/HTML/Perl-Weekly-Challenge/week-108-2.html)
 
diff --git a/challenge-108/abigail/awk/ch-2.awk b/challenge-108/abigail/awk/ch-2.awk
new file mode 100644
index 0000000000..96344e739e
--- /dev/null
+++ b/challenge-108/abigail/awk/ch-2.awk
@@ -0,0 +1,32 @@
+#!/usr/bin/awk
+
+#
+# See ../README.md
+#
+
+#
+# Run as: awk -f ch-2.awk [plain | compute]
+#
+
+BEGIN {
+    COUNT = 10
+    if (!ARGV [1] || ARGV [1] != "compute") {
+        printf "%s\n", "1, 1, 2, 5, 15, 52, 203, 877, 4140, 21147"
+    }
+    else {
+        bell [1, 1] = 1
+        for (x = 2; x < COUNT; x ++) {
+            bell [x, 1] = bell [x - 1, x - 1]
+            for (y = 2; y <= x; y ++) {
+                bell [x, y] = bell [x, y - 1] + bell [x - 1, y - 1]
+            }
+        }
+        printf "1"
+        for (x = 1; x < COUNT; x ++) {
+            printf ", %d", bell [x, x]
+        }
+        printf "\n"
+    }
+    delete ARGV
+}
+
diff --git a/challenge-108/abigail/bash/ch-2.sh b/challenge-108/abigail/bash/ch-2.sh
new file mode 100644
index 0000000000..c74aff4bbe
--- /dev/null
+++ b/challenge-108/abigail/bash/ch-2.sh
@@ -0,0 +1,43 @@
+#!/bin/sh
+
+#
+# See ../README.md
+#
+
+#
+# Run as: bash ch-2.sh
+#
+
+set -f
+
+COUNT=10
+
+function index () {
+    local x=$1
+    local y=$2
+    idx=$((COUNT * x + y))
+}
+
+
+if   [ "X$1" != "Xcompute" ]
+then echo "1, 1, 2, 5, 15, 52, 203, 877, 4140, 21147"
+else bell[0]=1
+     for ((x = 1; x < COUNT - 1; x ++))
+     do   index $x 0;                  i1=$idx
+          index $((x - 1)) $((x - 1)); i2=$idx
+          bell[$i1]=${bell[$i2]}
+          for ((y = 1; y <= x; y ++))
+          do  index   $x         $y;       i1=$idx
+              index   $x       $((y - 1)); i2=$idx
+              index $((x - 1)) $((y - 1)); i3=$idx
+              bell[$i1]=$((bell[i2] + bell[i3]))
+          done
+     done
+
+     printf "1"
+     for ((x = 0; x < COUNT - 1; x ++))
+     do index $x $x;
+        printf ", %d" ${bell[$idx]}
+     done
+     echo
+fi
diff --git a/challenge-108/abigail/basic/ch-2.bas b/challenge-108/abigail/basic/ch-2.bas
new file mode 100644
index 0000000000..2882082e94
--- /dev/null
+++ b/challenge-108/abigail/basic/ch-2.bas
@@ -0,0 +1,9 @@
+010 REM 
+020 REM See ../README.md
+030 REM 
+
+040 REM 
+050 REM Run as: basic ch-2.bas
+060 REM 
+
+100 PRINT "1, 1, 2, 5, 15, 52, 203, 877, 4140, 21147"
diff --git a/challenge-108/abigail/bc/ch-2.bc b/challenge-108/abigail/bc/ch-2.bc
new file mode 100644
index 0000000000..ba95c81011
--- /dev/null
+++ b/challenge-108/abigail/bc/ch-2.bc
@@ -0,0 +1,10 @@
+#
+# See ../README.md
+#
+
+#
+# Run as: bc ch-2.bc
+#
+"1, 1, 2, 5, 15, 52, 203, 877, 4140, 21147
+"
+quit
diff --git a/challenge-108/abigail/befunge-93/ch-2.bf93 b/challenge-108/abigail/befunge-93/ch-2.bf93
new file mode 100644
index 0000000000..b212d72728
--- /dev/null
+++ b/challenge-108/abigail/befunge-93/ch-2.bf93
@@ -0,0 +1,2 @@
+< v,_@#:<   "1, 1, 2, 5, 15, 52, 203, 877, 4140, 21147" +55
+  >     ^
diff --git a/challenge-108/abigail/blog.txt b/challenge-108/abigail/blog.txt
new file mode 100644
index 0000000000..ce18567b5c
--- /dev/null
+++ b/challenge-108/abigail/blog.txt
@@ -0,0 +1 @@
+https://abigail.github.io/HTML/Perl-Weekly-Challenge/week-108-1.html
diff --git a/challenge-108/abigail/blog1.txt b/challenge-108/abigail/blog1.txt
new file mode 100644
index 0000000000..575bff46c6
--- /dev/null
+++ b/challenge-108/abigail/blog1.txt
@@ -0,0 +1 @@
+https://abigail.github.io/HTML/Perl-Weekly-Challenge/week-108-2.html
diff --git a/challenge-108/abigail/c/ch-1.c b/challenge-108/abigail/c/ch-1.c
new file mode 100644
index 0000000000..0d1ad208bf
--- /dev/null
+++ b/challenge-108/abigail/c/ch-1.c
@@ -0,0 +1,21 @@
+# include <stdlib.h>
+# include <stdio.h>
+# include <string.h>
+
+/*
+ * See ../README.md
+ */
+
+/*
+ * Run as: cc -o ch-1.o ch-1.c; ./ch-1.o
+ */
+
+int main (void) {
+    int i;
+    printf ("%lld\n", (long long) &i); /* %p is specific for printing     */
+                                       /* memory addresses, but does this */
+                                       /* using hex numbers. So we cast   */
+                                       /* the address to long long and    */
+                                       /* print that.                     */
+    return (0);
+}
diff --git a/challenge-108/abigail/c/ch-2.c b/challenge-108/abigail/c/ch-2.c
new file mode 100644
index 0000000000..7d8352507b
--- /dev/null
+++ b/challenge-108/abigail/c/ch-2.c
@@ -0,0 +1,70 @@
+# include <stdlib.h>
+# include <stdio.h>
+# include <string.h>
+
+/*
+ * See ../README.md
+ */
+
+/*
+ * Run as: cc -o ch-2.o ch-2.c; ./ch-2.o
+ */
+
+# define COUNT   10
+
+# define PLAIN    0
+# define COMPUTE  2
+
+typedef int number;  /* Change if we want large numbers */
+char * fmt = "%d";   /* Should match typedef            */
+
+int main (int argc, char * argv []) {
+    int type = PLAIN;
+    if (argc > 1) {
+        if (strncmp (argv [1], "compute", 8) == 0) {
+            type = COMPUTE;
+        }
+    }
+
+    if (type == PLAIN) {
+        printf ("1, 1, 2, 5, 15, 52, 203, 877, 4140, 21147\n");
+    }
+    if (type == COMPUTE) {
+        /*
+         * Calculate the Bell triangle
+         */
+        number ** bell;
+        if ((bell = (number **) malloc ((COUNT - 1) * sizeof (number *)))
+            == NULL) {
+             perror ("Mallocing bell failed");
+             exit (1);
+        }
+        if ((bell [0] = (number *) malloc (sizeof (number))) == NULL) {
+            perror ("Mallocing row failed");
+            exit (1);
+        }
+        bell [0] [0] = 1;
+        for (int x = 1; x < COUNT - 1; x ++) {
+            if ((bell [x] = (number *) malloc ((x + 1) * sizeof (number)))
+                == NULL) {
+                perror ("Mallocing row failed");
+                exit (1);
+            }
+            bell [x] [0] = bell [x - 1] [x - 1];
+            for (int y = 1; y <= x; y ++) {
+                bell [x] [y] = bell [x] [y - 1] + bell [x - 1] [y - 1];
+            }
+        }
+
+        /*
+         * Print the right diagonal
+         */
+        printf (fmt, 1);
+        for (int x = 0; x < COUNT - 1; x ++) {
+            printf (", ");
+            printf (fmt, bell [x] [x]);
+        }
+        printf ("\n");
+    }
+    exit (0);
+}
diff --git a/challenge-108/abigail/cobol/ch-2.cb b/challenge-108/abigail/cobol/ch-2.cb
new file mode 100644
index 0000000000..c5aff7fdf8
--- /dev/null
+++ b/challenge-108/abigail/cobol/ch-2.cb
@@ -0,0 +1,14 @@
+IDENTIFICATION DIVISION.
+PROGRAM-ID. BELL.
+
+*>
+*> See ../README.md
+*>
+
+*>
+*> Run as: cobc -xF -o ch-2.o ch-2.cb; ./ch-2.o
+*>
+
+PROCEDURE DIVISION.
+    DISPLAY "1, 1, 2, 5, 15, 52, 203, 877, 4140, 21147".
+    STOP RUN.
diff --git a/challenge-108/abigail/csh/ch-2.csh b/challenge-108/abigail/csh/ch-2.csh
new file mode 100644
index 0000000000..ea424ce6b9
--- /dev/null
+++ b/challenge-108/abigail/csh/ch-2.csh
@@ -0,0 +1,11 @@
+#!/bin/csh
+
+#
+# See ../README.md
+#
+
+#
+# Run as: csh ch-2.csh
+#
+
+echo "1, 1, 2, 5, 15, 52, 203, 877, 4140, 21147"
diff --git a/challenge-108/abigail/erlang/ch-2.erl b/challenge-108/abigail/erlang/ch-2.erl
new file mode 100644
index 0000000000..f407e66fde
--- /dev/null
+++ b/challenge-108/abigail/erlang/ch-2.erl
@@ -0,0 +1,15 @@
+%
+% See ../README.md
+%
+
+%
+% Run as: ln ch-2.erl ch2.erl
+%         erl -compile ch2
+%         erl -noshell -s ch1 main -s init stop
+%
+
+-module (ch2).
+-export ([main/0]).
+
+main () ->
+    io:fwrite ("1, 1, 2, 5, 15, 52, 203, 877, 4140, 21147\n").
diff --git a/challenge-108/abigail/forth/ch-2.fs b/challenge-108/abigail/forth/ch-2.fs
new file mode 100644
index 0000000000..8b234c922e
--- /dev/null
+++ b/challenge-108/abigail/forth/ch-2.fs
@@ -0,0 +1,5 @@
+\
+\ See ../README.md
+\
+
+.( 1, 1, 2, 5, 15, 52, 203, 877, 4140, 21147)
diff --git a/challenge-108/abigail/fortran/ch-1.f90 b/challenge-108/abigail/fortran/ch-1.f90
new file mode 100644
index 0000000000..c55b81745e
--- /dev/null
+++ b/challenge-108/abigail/fortran/ch-1.f90
@@ -0,0 +1,13 @@
+!
+! See ../README.md
+!
+
+!
+! Run as: gfortran -o ch-1.o ch-1.f90; ./ch-1.o
+!
+
+program ch1
+    implicit none
+    integer :: i
+    print *, loc(i)
+end
diff --git a/challenge-108/abigail/fortran/ch-2.f90 b/challenge-108/abigail/fortran/ch-2.f90
new file mode 100644
index 0000000000..112f6f2cd0
--- /dev/null
+++ b/challenge-108/abigail/fortran/ch-2.f90
@@ -0,0 +1,12 @@
+!
+! See ../README.md
+!
+
+!
+! Run as: gfortran -o ch-2.o ch-2.f90; ./ch-2.o
+!
+
+program ch2
+    implicit none
+    write (*, *) "1, 1, 2, 5, 15, 52, 203, 877, 4140, 21147"
+end
diff --git a/challenge-108/abigail/go/ch-1.go b/challenge-108/abigail/go/ch-1.go
new file mode 100644
index 0000000000..fb3673f5f3
--- /dev/null
+++ b/challenge-108/abigail/go/ch-1.go
@@ -0,0 +1,16 @@
+package main
+
+//
+// See ../README.md
+//
+
+//
+// Run as: go run ch-1.go
+//
+
+import "fmt"
+
+func main () {
+    x := 0
+    fmt . Printf ("%d\n", &x)
+}
diff --git a/challenge-108/abigail/go/ch-2.go b/challenge-108/abigail/go/ch-2.go
new file mode 100644
index 0000000000..ef6ebae1a6
--- /dev/null
+++ b/challenge-108/abigail/go/ch-2.go
@@ -0,0 +1,15 @@
+package main
+
+//
+// See ../README.md
+//
+
+//
+// Run as: go run ch-1.go
+//
+
+import "fmt"
+
+func main () {
+    fmt . Print ("1, 1, 2, 5, 15, 52, 203, 877, 4140, 21147\n")
+}
diff --git a/challenge-108/abigail/java/ch-2.java b/challenge-108/abigail/java/ch-2.java
new file mode 100644
index 0000000000..71c3980ce9
--- /dev/null
+++ b/challenge-108/abigail/java/ch-2.java
@@ -0,0 +1,13 @@
+//
+// See ../README.md
+//
+
+//
+// Run as: ln ch-2.java ch2.java; javac ch2; java ch2
+//
+
+public class ch2 {
+    public static void main (String [] args) {
+        System . out . print ("1, 1, 2, 5, 15, 52, 203, 877, 4140, 21147\n");
+    }
+}
diff --git a/challenge-108/abigail/lua/ch-2.lua b/challenge-108/abigail/lua/ch-2.lua
new file mode 100644
index 0000000000..37f067c465
--- /dev/null
+++ b/challenge-108/abigail/lua/ch-2.lua
@@ -0,0 +1,41 @@
+#!/opt/local/bin/lua
+
+--
+-- See ../README.md
+--
+
+--
+-- Run as: lua ch-2.lua
+--
+
+local COUNT   = 10
+local PLAIN   =  0
+local COMPUTE =  1
+
+local type = PLAIN
+if   #arg >= 1 and arg [1] == "compute"
+then type = COMPUTE
+end
+
+if   type == PLAIN
+then print ("1, 1, 2, 5, 15, 52, 203, 877, 4140, 21147")
+end
+
+if   type == COMPUTE
+then local bell = {}
+     bell [0] = {}
+     bell [0] [0] = 1
+     for x = 1, COUNT - 2
+     do  bell [x] = {}
+         bell [x] [0] = bell [x - 1] [x - 1]
+         for  y = 1, x
+         do   bell [x] [y] = bell [x] [y - 1] + bell [x - 1] [y - 1]
+         end
+     end
+
+     io . write (1)
+     for x = 0, COUNT - 2
+     do  io . write (", " .. bell [x] [x])
+     end
+     io . write ("\n")
+end
diff --git a/challenge-108/abigail/m4/ch-2.m4 b/challenge-108/abigail/m4/ch-2.m4
new file mode 100644
index 0000000000..52ad7f9d63
--- /dev/null
+++ b/challenge-108/abigail/m4/ch-2.m4
@@ -0,0 +1 @@
+1, 1, 2, 5, 15, 52, 203, 877, 4140, 21147
diff --git a/challenge-108/abigail/node/ch-2.js b/challenge-108/abigail/node/ch-2.js
n