Push updated code

Integrity/Branch.cs

@@ -0,0 +1,38 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace LibZNI.Integrity
+{
+    internal class Branch
+    {
+        private Leaf lA;
+        private Leaf lB;
+
+        public Branch(Leaf a, Leaf b)
+        {
+            lA = a;
+            lB = b;
+        }
+
+        public byte[] GetNodeHash()
+        {
+            byte[] h1 = Tools.SHA256HashBytes(lA.InputBytes);
+            byte[] h2 = Tools.SHA256HashBytes(lB.InputBytes);
+
+            byte[] h3 = new byte[h1.Length + h2.Length];
+            h1.CopyTo(h3, 0);
+            h2.CopyTo(h3, h1.Length);
+
+            byte[] b = Tools.SHA256HashBytes(Tools.SHA256HashBytes(h3));
+            return b;
+        }
+        public override string ToString()
+        {
+            byte[] i = GetNodeHash();
+            return Tools.Hash2String(i);
+        }
+    }
+}