1 files changed, 8 insertions, 0 deletions
diff --git a/src/2017/day10/aoc.h b/src/2017/day10/aoc.h
index 9fea13e..a4cdca8 100644
--- a/src/2017/day10/aoc.h
+++ b/src/2017/day10/aoc.h
@@ -3,5 +3,13 @@
 #include <vector>
 
 namespace aoc2017 {
+
+struct knot {
+  int val;
+  knot* next = nullptr;
+  knot* prev = nullptr;
+};
+
+
 std::pair<int64_t, int64_t> day10(line_view);
 }