From ca83d5724f04a269fa8f2c6407a1f73ab60911c1 Mon Sep 17 00:00:00 2001
From: Christoph Urlacher <christoph.urlacher@protonmail.com>
Date: Fri, 20 Feb 2026 00:07:42 +0100
Subject: [PATCH] fix BlockIterator always starting at pos 0 (even if there's
 no Block there)

---
 include/klotski.hpp | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/include/klotski.hpp b/include/klotski.hpp
index f6bc291..5c8bcba 100644
--- a/include/klotski.hpp
+++ b/include/klotski.hpp
@@ -237,7 +237,13 @@ public:
 
   bool operator!=(const State &other) const { return !(*this == other); }
 
-  BlockIterator begin() const { return BlockIterator(*this); }
+  BlockIterator begin() const {
+    BlockIterator it = BlockIterator(*this);
+    if (!(*it).IsValid()) {
+      ++it;
+    }
+    return it;
+  }
 
   BlockIterator end() const { return BlockIterator(*this, width * height); }