chk for empty tree

Author: justcoding121

Advanced.Algorithms/DataStructures/Tree/B+Tree.cs

@@ -75,6 +75,8 @@ public T Max
         {
             get
             {
+                if (Root == null) return default(T);
+
                 var maxNode = findMaxNode(Root);
                 return maxNode.Keys[maxNode.KeyCount - 1];
             }
@@ -84,6 +86,8 @@ public T Min
         {
             get
             {
+                if (Root == null) return default(T);
+
                 var minNode = BottomLeftNode;
                 return minNode.Keys[0];
             }

Advanced.Algorithms/DataStructures/Tree/BTree.cs

@@ -100,6 +100,8 @@ public T Max
         {
             get
             {
+                if (Root == null) return default(T);
+
                 var maxNode = findMaxNode(Root);
                 return maxNode.Keys[maxNode.KeyCount - 1];
             }
@@ -109,6 +111,8 @@ public T Min
         {
             get
             {
+                if (Root == null) return default(T);
+
                 var minNode = findMinNode(Root);
                 return minNode.Keys[0];
             }