diff --git a/Util/geometry.h b/Util/geometry.h
index 980fb30..506298f 100644
--- a/Util/geometry.h
+++ b/Util/geometry.h
@@ -1,3 +1,5 @@
+#pragma once
+
 #include <vector>
 
 // Forward declarations
@@ -24,7 +26,7 @@ struct Vector {
     }
 
     Vector cross(const Vector &other) {
-        return Vector(c[1] * other[2] - c[2] - other[1], c[2] * other[0] - c[0] * other[2],
+        return Vector(c[1] * other[2] - c[2] * other[1], c[2] * other[0] - c[0] * other[2],
                       c[0] * other[1] - c[1] * other[0]);
     }