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diff --git a/boost/container/detail/next_capacity.hpp b/boost/container/detail/next_capacity.hpp
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+//////////////////////////////////////////////////////////////////////////////
+//
+// (C) Copyright Ion Gaztanaga 2014-2015. Distributed under 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)
+//
+// See http://www.boost.org/libs/container for documentation.
+//
+//////////////////////////////////////////////////////////////////////////////
+#ifndef BOOST_CONTAINER_DETAIL_NEXT_CAPACITY_HPP
+#define BOOST_CONTAINER_DETAIL_NEXT_CAPACITY_HPP
+
+#ifndef BOOST_CONFIG_HPP
+#  include <boost/config.hpp>
+#endif
+
+#if defined(BOOST_HAS_PRAGMA_ONCE)
+#  pragma once
+#endif
+
+// container
+#include <boost/container/throw_exception.hpp>
+// container/detail
+#include <boost/container/detail/min_max.hpp>
+
+namespace boost {
+namespace container {
+namespace container_detail {
+
+enum NextCapacityOption { NextCapacityDouble, NextCapacity60Percent };
+
+template<class SizeType, NextCapacityOption Option>
+struct next_capacity_calculator;
+
+template<class SizeType>
+struct next_capacity_calculator<SizeType, NextCapacityDouble>
+{
+   static SizeType get(const SizeType max_size
+                      ,const SizeType capacity
+                      ,const SizeType n)
+   {
+      const SizeType remaining = max_size - capacity;
+      if ( remaining < n )
+         boost::container::throw_length_error("get_next_capacity, allocator's max_size reached");
+      const SizeType additional = max_value(n, capacity);
+      return ( remaining < additional ) ? max_size : ( capacity + additional );
+   }
+};
+
+template<class SizeType>
+struct next_capacity_calculator<SizeType, NextCapacity60Percent>
+{
+   static SizeType get(const SizeType max_size
+                     ,const SizeType capacity
+                     ,const SizeType n)
+   {
+      const SizeType remaining = max_size - capacity;
+      if ( remaining < n )
+         boost::container::throw_length_error("get_next_capacity, allocator's max_size reached");
+      const SizeType m3 = max_size/3;
+
+      if (capacity < m3)
+         return capacity + max_value(3*(capacity+1)/5, n);
+
+      if (capacity < m3*2)
+         return capacity + max_value((capacity+1)/2, n);
+      return max_size;
+   }
+};
+
+}  //namespace container_detail {
+}  //namespace container {
+}  //namespace boost {
+
+#endif   //#ifndef BOOST_CONTAINER_DETAIL_NEXT_CAPACITY_HPP