From 25c1ddbeddeda95bb01f211ef25df57262eab3d1 Mon Sep 17 00:00:00 2001
From: setop <setop@zoocoop.com>
Date: Tue, 6 Dec 2022 20:00:50 +0100
Subject: [PATCH] day 6, AWK solution

---
 d06/exec.awk | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)
 create mode 100644 d06/exec.awk

diff --git a/d06/exec.awk b/d06/exec.awk
new file mode 100644
index 0000000..169f80f
--- /dev/null
+++ b/d06/exec.awk
@@ -0,0 +1,18 @@
+BEGIN { W = 14 }
+{
+	for (i=1; i<=length($1); i++) {
+		window = substr($1,i,W)
+		# compare each char of window to all char of window
+		S = 0  # to count match
+		for (j=1; j<=W; j++) {
+			for (k=1; k<=W; k++) {
+				S+= (substr(window,j,1) == substr(window,k,1)) ? 1 : 0
+			}
+		}
+		# if each char match only with itsef
+		if (S == W) {
+			print i + W - 1
+			next  # finish
+		}
+	}
+}
\ No newline at end of file