AWK solution for week 097, part 1

1 files changed, 53 insertions, 0 deletions

diff --git a/challenge-097/abigail/awk/ch-1.awk b/challenge-097/abigail/awk/ch-1.awk
new file mode 100644
index 0000000000..a33507ee33
--- /dev/null
+++ b/challenge-097/abigail/awk/ch-1.awk
@@ -0,0 +1,53 @@
+#!/usr/bin/awk
+
+#
+# See ../README.md
+#
+
+#
+# Run as: awk -f ch-1.awk -s SHIFT < input-file
+#
+
+BEGIN {
+    NR_OF_LETTERS = 26
+    ORD_A         = 65
+
+    #
+    # Create a letter to number mapping
+    #
+    for (i = ORD_A; i < ORD_A + NR_OF_LETTERS; i ++) {
+        t = sprintf ("%c", i)
+        ord [t] = i
+    }
+
+    #
+    # Parse command line
+    #
+    for (i = 1; i < ARGC; i ++) {
+        if (ARGV [i] == "-s") {
+            shift = ARGV [i + 1]
+        }
+    }
+    ARGC = 0
+}
+
+{
+    split($0, letters, "")
+    out = ""
+    #
+    # Iterate over the individual letters, shifting capital letters
+    #
+    for (i = 1; i <= length (letters); i ++) {
+        char = letters [i]
+        if (ord [char]) {
+            n = ord [char] - shift
+            if (n < ORD_A) {
+                n = n + NR_OF_LETTERS
+            }
+            char = sprintf ("%c", n)
+        }
+        out = out char
+    }
+    print out
+}
+