From afb90dd6756afcd43a86249358fe3a41e3cf1950 Mon Sep 17 00:00:00 2001
From: Abigail <abigail@abigail.be>
Date: Mon, 18 Oct 2021 20:20:18 +0200
Subject: AWK solutions for week 135

---
 challenge-135/abigail/README.md    |  2 ++
 challenge-135/abigail/awk/ch-1.awk | 28 ++++++++++++++++++++++++++++
 challenge-135/abigail/awk/ch-2.awk | 38 ++++++++++++++++++++++++++++++++++++++
 3 files changed, 68 insertions(+)
 create mode 100644 challenge-135/abigail/awk/ch-1.awk
 create mode 100644 challenge-135/abigail/awk/ch-2.awk

diff --git a/challenge-135/abigail/README.md b/challenge-135/abigail/README.md
index 6c58ec0530..e0e26b70dd 100644
--- a/challenge-135/abigail/README.md
+++ b/challenge-135/abigail/README.md
@@ -2,10 +2,12 @@
 
 ## Part 1
 
+* [AWK](awk/ch-1.awk)
 * [C](c/ch-1.c)
 * [Perl](perl/ch-1.pl)
 
 ## Part 2
 
+* [AWK](awk/ch-2.awk)
 * [C](c/ch-2.c)
 * [Perl](perl/ch-2.pl)
diff --git a/challenge-135/abigail/awk/ch-1.awk b/challenge-135/abigail/awk/ch-1.awk
new file mode 100644
index 0000000000..210b27b9b0
--- /dev/null
+++ b/challenge-135/abigail/awk/ch-1.awk
@@ -0,0 +1,28 @@
+#!/usr/bin/awk
+
+#
+# See ../README.md
+#
+
+#
+# Run as: awk -f ch-1.awk < input-file
+#
+
+
+#
+# Get rid of leading sign
+#
+/^[-+]/         {$0 = substr ($0, 2)}
+
+#
+# Validation
+#
+/[^0-9]/        {print "not an integer";        next}
+/^(..)*$/       {print "even number of digits"; next}
+length ($0) < 3 {print "too short";             next}
+
+#
+# Print the middle three digits
+#
+
+                {print substr ($0, 1 + int ((length ($0) - 3) / 2), 3)}
diff --git a/challenge-135/abigail/awk/ch-2.awk b/challenge-135/abigail/awk/ch-2.awk
new file mode 100644
index 0000000000..021224dfe0
--- /dev/null
+++ b/challenge-135/abigail/awk/ch-2.awk
@@ -0,0 +1,38 @@
+#!/usr/bin/awk
+
+#
+# See ../README.md
+#
+
+#
+# Run as: awk -f ch-2.awk < input-file
+#
+
+BEGIN {
+    split ("1 3 1 7 3 9 1", w, " ")
+    for (i = 48; i <= 57; i ++) {
+        c [sprintf ("%c", i)] = i - 48
+    }
+    for (i = 65; i <= 90; i ++) {
+        c [sprintf ("%c", i)] = i - 65
+    }
+}
+
+
+#
+# Check for the right characters, and the correct length.
+#
+/[^0-9BCDFGHJKLMNPQRSTVWXYZ]/ {print 0; next}
+length ($0) != 7              {print 0; next}
+
+#
+# Do the check sum
+#
+{
+    check = 0
+    for (i = 1; i <= 7; i ++) {
+        check += w [i] * c [substr ($0, i, 1)]
+    }
+    print (check % 10 == 0 ? 1 : 0)
+}
+    
-- 
cgit