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+// Copyright 2005 The Trustees of Indiana University.
+
+// Use, modification and distribution is subject to the Boost Software
+// License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
+// http://www.boost.org/LICENSE_1_0.txt)
+
+//  Authors: Douglas Gregor
+//           Andrew Lumsdaine
+
+#ifndef BOOST_GRAPH_PARALLEL_INPLACE_ALL_TO_ALL_HPP
+#define BOOST_GRAPH_PARALLEL_INPLACE_ALL_TO_ALL_HPP
+
+#ifndef BOOST_GRAPH_USE_MPI
+#error "Parallel BGL files should not be included unless <boost/graph/use_mpi.hpp> has been included"
+#endif
+
+//
+// Implements the inplace all-to-all communication algorithm.
+//
+#include <vector>
+#include <iterator>
+
+namespace boost { namespace parallel { 
+
+template<typename ProcessGroup, typename T>
+// where {LinearProcessGroup<ProcessGroup>, MessagingProcessGroup<ProcessGroup>}
+void 
+inplace_all_to_all(ProcessGroup pg, 
+                   const std::vector<std::vector<T> >& outgoing,
+                   std::vector<std::vector<T> >& incoming)
+{
+  typedef typename std::vector<T>::size_type size_type;
+
+  typedef typename ProcessGroup::process_size_type process_size_type;
+  typedef typename ProcessGroup::process_id_type process_id_type;
+
+  process_size_type p = num_processes(pg);
+
+  // Make sure there are no straggling messages
+  synchronize(pg);
+
+  // Send along the count (always) and the data (if count > 0)
+  for (process_id_type dest = 0; dest < p; ++dest) {
+    if (dest != process_id(pg)) {
+      send(pg, dest, 0, outgoing[dest].size());
+      if (!outgoing[dest].empty())
+        send(pg, dest, 1, &outgoing[dest].front(), outgoing[dest].size());
+    }
+  }
+
+  // Make sure all of the data gets transferred
+  synchronize(pg);
+
+  // Receive the sizes and data
+  for (process_id_type source = 0; source < p; ++source) {
+    if (source != process_id(pg)) {
+      size_type size;
+      receive(pg, source, 0, size);
+      incoming[source].resize(size);
+      if (size > 0)
+        receive(pg, source, 1, &incoming[source].front(), size);
+    } else if (&incoming != &outgoing) {
+      incoming[source] = outgoing[source];
+    }
+  }
+}
+
+template<typename ProcessGroup, typename T>
+// where {LinearProcessGroup<ProcessGroup>, MessagingProcessGroup<ProcessGroup>}
+void 
+inplace_all_to_all(ProcessGroup pg, std::vector<std::vector<T> >& data)
+{
+  inplace_all_to_all(pg, data, data);
+}
+
+} } // end namespace boost::parallel
+
+#endif // BOOST_GRAPH_PARALLEL_INPLACE_ALL_TO_ALL_HPP