diff --git a/Graph/Edge.cs b/Graph/Edge.cs
index 9cfa252..0c35cbd 100644
--- a/Graph/Edge.cs
+++ b/Graph/Edge.cs
@@ -3,8 +3,8 @@
     public struct Edge
     {
         public Node neighbor { get; }
-        public double weight { get; }
-        public Edge(Node neighbor, double weight)
+        public float weight { get; }
+        public Edge(Node neighbor, float weight)
         {
             this.neighbor = neighbor;
             this.weight = weight;
diff --git a/Graph/Node.cs b/Graph/Node.cs
index 23ab811..433f884 100644
--- a/Graph/Node.cs
+++ b/Graph/Node.cs
@@ -4,21 +4,21 @@
     {
         public float lat { get; }
         public float lon { get; }
-        public List<Edge> edges { get; }
+        public HashSet<Edge> edges { get; }
 
         public Node previousNode { get; set; }
-        public double goalDistance { get; set; }
+        public float goalDistance { get; set; }
 
-        public double pathLength { get; set; }
+        public float pathLength { get; set; }
 
         public Node(float lat, float lon)
         {
             this.lat = lat;
             this.lon = lon;
-            this.edges = new List<Edge>();
+            this.edges = new();
             this.previousNode = nullnode;
-            this.goalDistance = double.MaxValue;
-            this.pathLength = double.MaxValue;
+            this.goalDistance = float.MaxValue;
+            this.pathLength = float.MaxValue;
         }
         public static Node nullnode = new(float.NaN, float.NaN);
     }
diff --git a/Graph/Utils.cs b/Graph/Utils.cs
index 6240448..550ed10 100644
--- a/Graph/Utils.cs
+++ b/Graph/Utils.cs
@@ -2,12 +2,12 @@
 
     public struct Utils
     {
-        public static double DistanceBetweenNodes(Node n1, Node n2)
+        public static float DistanceBetweenNodes(Node n1, Node n2)
         {
             return DistanceBetweenCoordinates(n1.lat, n1.lon, n2.lat, n2.lon);
         }
 
-        public static double DistanceBetweenCoordinates(float lat1, float lon1, float lat2, float lon2)
+        public static float DistanceBetweenCoordinates(float lat1, float lon1, float lat2, float lon2)
         {
             const int earthRadius = 6371;
             double differenceLat = DegreesToRadians(lat2 - lat1);
@@ -19,7 +19,7 @@
             double a = Math.Sin(differenceLat / 2) * Math.Sin(differenceLat / 2) + Math.Sin(differenceLon / 2) * Math.Sin(differenceLon / 2) * Math.Cos(lat1Rads) * Math.Cos(lat2Rads);
             double c = 2 * Math.Atan2(Math.Sqrt(a), Math.Sqrt(1 - a));
 
-            return earthRadius * c;
+            return Convert.ToSingle(earthRadius * c);
         }
 
         private static double DegreesToRadians(double deg)
diff --git a/astar/Astar.cs b/astar/Astar.cs
index 6019cb5..187afaa 100644
--- a/astar/Astar.cs
+++ b/astar/Astar.cs
@@ -34,7 +34,7 @@ namespace astar
             foreach(Node n in nodes.Values)
             {
                 n.previousNode = Node.nullnode;
-                n.goalDistance = double.MaxValue;
+                n.goalDistance = float.MaxValue;
             }
         }