diff --git a/sirius.cpp b/sirius.cpp
index 7e4da9549e45508c455c456482ff24e67129a5d4..756eec73c52e2233b54537735ed107667a8f7599 100644
--- a/sirius.cpp
+++ b/sirius.cpp
@@ -198,18 +198,14 @@ public:
 
 };
 
-inline float lengthv2(vec2 v) {
-  return sqrt(v.x * v.x + v.y * v.y);
-}
-
-inline float crossv2(vec2 a, vec2 b) {
-  return a.x * b.y - a.y * b.x;
+inline float cross(vec2 a, vec2 b) {
+    return a.x * b.y - a.y * b.x;
 }
 
 inline bool onDifferentSides(vec2 p1, vec2 p2, vec2 q1, vec2 q2) {
   vec2 v = p2-p1;
   vec2 r = p1;
-  return lengthv2(crossv2(v, p1 - r) * crossv2(v, p2 - r)) < 0;
+    return cross(v, p1 - r) * cross(v, p2 - r) < 0;
 }
 
 inline bool intersectEachOther(vec2 p1, vec2 p2, vec2 q1, vec2 q2) {