Index: trunk/BNC/bnccomb.h
===================================================================
--- trunk/BNC/bnccomb.h	(revision 3373)
+++ trunk/BNC/bnccomb.h	(revision 3373)
@@ -0,0 +1,63 @@
+
+#ifndef BNCCOMB_H
+#define BNCCOMB_H
+
+template <class BidIt>
+inline bool next_combination(BidIt n_begin, BidIt n_end, 
+                             BidIt r_begin, BidIt r_end) {
+  
+  bool boolmarked=false;
+  BidIt r_marked;
+  
+  BidIt n_it1=n_end;
+  --n_it1;
+  
+  
+  BidIt tmp_r_end=r_end;
+  --tmp_r_end;
+  
+  for(BidIt r_it1=tmp_r_end; r_it1!=r_begin || r_it1==r_begin; --r_it1,--n_it1)
+  {
+    if(*r_it1==*n_it1 )
+    {
+      if(r_it1!=r_begin) //to ensure not at the start of r sequence
+      {
+        boolmarked=true;
+        r_marked=(--r_it1);
+        ++r_it1;//add it back again 
+        continue;
+      }
+      else // it means it is at the start the sequence, so return false
+        return false;      
+    }
+    else //if(*r_it1!=*n_it1 )
+    {
+      //marked code
+      if(boolmarked==true)
+      {
+        //for loop to find which marked is in the first sequence
+        BidIt n_marked;//mark in first sequence
+        for (BidIt n_it2=n_begin;n_it2!=n_end;++n_it2)
+          if(*r_marked==*n_it2) {n_marked=n_it2;break;}
+      
+    
+        BidIt n_it3=++n_marked;    
+        for  (BidIt r_it2=r_marked;r_it2!=r_end;++r_it2,++n_it3)
+        {
+          *r_it2=*n_it3;
+        }
+        return true;
+      }
+      for(BidIt n_it4=n_begin; n_it4!=n_end; ++n_it4)
+        if(*r_it1==*n_it4)
+        {
+          *r_it1=*(++n_it4);
+          return true;           
+        }
+    }
+  }  
+
+  return true;//will never reach here    
+}
+
+#endif