From 2e28981207430301b54d4d74ee620d0f159f4d8b Mon Sep 17 00:00:00 2001
From: Thomas Voss <thomasvoss@live.com>
Date: Sun, 5 Dec 2021 10:37:21 +0100
Subject: Add day 3 solutions

---
 2017/03/puzzle-2.awk | 38 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 38 insertions(+)
 create mode 100755 2017/03/puzzle-2.awk

(limited to '2017/03/puzzle-2.awk')

diff --git a/2017/03/puzzle-2.awk b/2017/03/puzzle-2.awk
new file mode 100755
index 0000000..0758658
--- /dev/null
+++ b/2017/03/puzzle-2.awk
@@ -0,0 +1,38 @@
+#!/usr/bin/env -S awk -f
+
+function move(xi, yi)
+{
+	for (k = 0; k < j; k++) {
+		if (xi)
+			x += xi
+		else
+			y += yi
+
+		spiral[y][x] = spiral[y][x - 1] + spiral[y][x + 1] + spiral[y + 1][x + 1] \
+				+ spiral[y + 1][x] + spiral[y + 1][x - 1] + spiral[y - 1][x + 1] \
+				+ spiral[y - 1][x] + spiral[y - 1][x - 1]
+		if (spiral[y][x] > n)
+			return spiral[y][x]
+	}
+	return 0
+}
+
+{ n = $1 }
+
+END {
+	spiral[0][0] = 1
+	x = y = 0
+	j = 1
+	for (i = 1; 1; i++) {
+		if (i % 2)
+			if (r = move(j % 2 ? 1 : -1, 0))
+				break
+		else {
+			if (r = move(0, j % 2 ? 1 : -1))
+				break
+			j++
+		}
+	}
+
+	print r
+}
-- 
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