Merge pull request #4812 from dcw803/master

imported this week's tasks - two pretty easy tasks this week

4 files changed, 154 insertions, 45 deletions

diff --git a/challenge-127/duncan-c-white/README b/challenge-127/duncan-c-white/README
index aa79957d19..bc6fe8dd99 100644
--- a/challenge-127/duncan-c-white/README
+++ b/challenge-127/duncan-c-white/README
@@ -1,57 +1,57 @@
-Task 1: "Count Numbers
+Task 1: "Disjoint Sets
 
-You are given a positive integer $N.
+You are given two sets with unique integers.
 
-Write a script to print count of numbers from 1 to $N that don't
-contain digit 1.
+Write a script to figure out if they are disjoint.
 
-Example
-
-Input: $N = 15
-Output: 8
+The two sets are disjoint if they don't have any common members.
 
-    There are 8 numbers between 1 and 15 that don't contain digit 1.
-    2, 3, 4, 5, 6, 7, 8, 9.
+Example
 
-Input: $N = 25
-Output: 13
+  Input: @S1 = (1, 2, 5, 3, 4)
+         @S2 = (4, 6, 7, 8, 9)
+  Output: 0 as the given two sets have common member 4.
 
-    There are 13 numbers between 1 and 25 that don't contain digit 1.
-    2, 3, 4, 5, 6, 7, 8, 9, 20, 22, 23, 24, 25.
+  Input: @S1 = (1, 3, 5, 7, 9)
+         @S2 = (0, 2, 4, 6, 8)
+  Output: 1 as the given two sets do not have common member.
 "
 
-My notes: very easy.  Let's produce the "There are ..." output if --debug
-is given, the terse output otherwise.
-
+My notes: very easy:  Intersection is not empty.
 
-Task 2: "Minesweeper Game
 
-You are given a rectangle with points marked with either x or *.
-Please consider the x as a land mine (DCW adds: and a * as a non-landmine).
+Task 2: "Conflict Intervals
 
-Write a script to print a rectangle with numbers and x as in the
-Minesweeper game.
+You are given a list of intervals.
 
-A number in a square of the minesweeper game indicates the number
-of mines within the neighbouring squares (usually 8), also implies
-that there are no bombs on that square.
+Write a script to find out if the current interval conflicts with any
+of the previous intervals.
 
 Example
 
-Input:
-    x * * * x * x x x x
-    * * * * * * * * * x
-    * * * * x * x * x *
-    * * * x x * * * * *
-    x * * * x * * * * x
-
-Output:
-    x 1 0 1 x 2 x x x x
-    1 1 0 2 2 4 3 5 5 x
-    0 0 1 3 x 3 x 2 x 2
-    1 1 1 x x 4 1 2 2 2
-    x 1 1 3 x 2 0 0 1 x
+Input: @Intervals = [ (1,4), (3,5), (6,8), (12, 13), (3,20) ]
+Output: [ (3,5), (3,20) ]
+
+    - The 1st interval (1,4) have no previous intervals to compare, skip it.
+    - The 2nd interval (3,5) conflicts with previous interval (1,4).
+    - The 3rd interval (6,8) does not conflict with any of the previous
+      intervals (1,4) and (3,5), so skip it.
+    - The 4th interval (12,13) again does not conflict with any of the
+      previous intervals (1,4), (3,5) and (6,8), so skip it.
+    - The 5th interval (3,20) conflicts with the first interval (1,4).
+
+Input: @Intervals = [ (3,4), (5,7), (6,9), (10, 12), (13,15) ]
+Output: [ (6,9) ]
+
+    - The 1st interval (3,4) has no previous intervals to compare, skip it.
+    - The 2nd interval (5,7) does not conflict with the previous interval
+      (3,4), so skip it.
+    - The 3rd interval (6,9) does conflict with one of the previous intervals
+      (5,7).
+    - The 4th interval (10,12) do not conflicts with any of the previous
+      intervals (3,4), (5,7) and (6,9), so skip it.
+    - The 5th interval (13,15) do not conflicts with any of the previous
+      intervals (3,4), (5,7), (6,9) and (10,12), so skip it.
 "
 
-My notes: also looks pretty easy.  It's not the WHOLE minesweeper game,
-just the "work out what the finished puzzle looks like"
+My notes: also looks pretty easy.  I think "conflict" means "overlap".
diff --git a/challenge-127/duncan-c-white/perl/ch-1.pl b/challenge-127/duncan-c-white/perl/ch-1.pl
new file mode 100755
index 0000000000..3e3e2cb4ee
--- /dev/null
+++ b/challenge-127/duncan-c-white/perl/ch-1.pl
@@ -0,0 +1,37 @@
+#!/usr/bin/perl
+# 
+# Task 1: "Disjoint Sets
+# 
+# You are given two sets with unique integers.
+# 
+# Write a script to figure out if they are disjoint.
+# 
+# The two sets are disjoint if they don't have any common members.
+# 
+# Example
+# 
+#   Input: @S1 = (1, 2, 5, 3, 4)
+#          @S2 = (4, 6, 7, 8, 9)
+#   Output: 0 as the given two sets have common member 4.
+# 
+#   Input: @S1 = (1, 3, 5, 7, 9)
+#          @S2 = (0, 2, 4, 6, 8)
+#   Output: 1 as the given two sets do not have common member.
+# "
+# 
+# My notes: very easy:  Intersection is not empty.
+# 
+
+use strict;
+use warnings;
+use feature 'say';
+use Getopt::Long;
+#use Data::Dumper;
+
+my $debug=0;
+die "Usage: disjoint-sets [-d|--debug] SET1 SET2\n" unless
+	GetOptions( "debug"=>\$debug ) && @ARGV==2;
+my %s1 = map { $_ => 1 } split(/,/,$ARGV[0]);
+my @common = grep { $s1{$_} } split(/,/,$ARGV[1]);
+say join(',',@common) if $debug && @common;
+say( (@common==0)?1:0);
diff --git a/challenge-127/duncan-c-white/perl/ch-2.pl b/challenge-127/duncan-c-white/perl/ch-2.pl
new file mode 100755
index 0000000000..be60937942
--- /dev/null
+++ b/challenge-127/duncan-c-white/perl/ch-2.pl
@@ -0,0 +1,77 @@
+#!/usr/bin/perl
+# 
+# Task 2: "Conflict Intervals
+# 
+# You are given a list of intervals.
+# 
+# Write a script to find out if the current interval conflicts with any
+# of the previous intervals.
+# 
+# Example
+# 
+# Input: @Intervals = [ (1,4), (3,5), (6,8), (12, 13), (3,20) ]
+# Output: [ (3,5), (3,20) ]
+# 
+#     - The 1st interval (1,4) have no previous intervals to compare, skip it.
+#     - The 2nd interval (3,5) conflicts with previous interval (1,4).
+#     - The 3rd interval (6,8) does not conflict with any of the previous
+#       intervals (1,4) and (3,5), so skip it.
+#     - The 4th interval (12,13) again does not conflict with any of the
+#       previous intervals (1,4), (3,5) and (6,8), so skip it.
+#     - The 5th interval (3,20) conflicts with the first interval (1,4).
+# 
+# Input: @Intervals = [ (3,4), (5,7), (6,9), (10, 12), (13,15) ]
+# Output: [ (6,9) ]
+# 
+#     - The 1st interval (3,4) has no previous intervals to compare, skip it.
+#     - The 2nd interval (5,7) does not conflict with the previous interval
+#       (3,4), so skip it.
+#     - The 3rd interval (6,9) does conflict with one of the previous intervals
+#       (5,7).
+#     - The 4th interval (10,12) do not conflicts with any of the previous
+#       intervals (3,4), (5,7) and (6,9), so skip it.
+#     - The 5th interval (13,15) do not conflicts with any of the previous
+#       intervals (3,4), (5,7), (6,9) and (10,12), so skip it.
+# "
+# 
+# My notes: also looks pretty easy.  I think "conflict" means "overlap".
+# 
+# 
+
+use strict;
+use warnings;
+use feature 'say';
+use Function::Parameters;
+use Getopt::Long;
+use Data::Dumper;
+
+my $debug = 0;
+
+die "Usage: overlap [-d|--debug] list(from,to) pairs\n"
+	unless GetOptions( "debug"=>\$debug ) && @ARGV>0;
+my @overlap = overlap( @ARGV );
+say join(' ',@overlap);
+
+
+#
+# my @overlap = overlap( @pair );
+#	Determine whether any of @pair intervals overlap;
+#	return a list of those that do overlap.
+#
+fun overlap( @pair )
+{
+	my @line;
+	my @result;
+	foreach my $xy (@pair)
+	{
+		my( $a, $b  ) = split(/,/,$xy);
+		my $add = 0;
+		foreach my $pos ($a..$b)
+		{
+			$add++ if $line[$pos];
+			$line[$pos] = 1;
+		}
+		push @result, $xy if $add;
+	}
+	return @result;
+}
diff --git a/challenge-127/duncan-c-white/perl/minesweeper.in b/challenge-127/duncan-c-white/perl/minesweeper.in
deleted file mode 100644
index acf700e3c2..0000000000
--- a/challenge-127/duncan-c-white/perl/minesweeper.in
+++ /dev/null
@@ -1,5 +0,0 @@
-     x * * * x * x x x x
-    * * * * *       * * * * x
-   * * * * x * x * x *
-  * *   * x x * *    * * *
- x * * * x * * * * x