libs/circular_buffer/example/circular_buffer_sum_example.cpp

// Copyright 2003-2008 Jan Gaspar.
// Copyright 2013 Paul A. Bristow.   Added some Quickbook snippet markers.
// Distributed under the Boost Software License, Version 1.0.
// (See the accompanying file LICENSE_1_0.txt
// or a copy at <http://www.boost.org/LICENSE_1_0.txt>.)
//[circular_buffer_sum_example_1
/*`This example shows several functions, including summing all valid values.
*/
   #include <boost/circular_buffer.hpp>
   #include <numeric>
   #include <assert.h>
   int main(int /*argc*/, char* /*argv*/[])
   {
      // Create a circular buffer of capacity 3.
      boost::circular_buffer<int> cb(3);
      assert(cb.capacity() == 3);
      // Check is empty.
      assert(cb.size() == 0);
      assert(cb.empty());
      // Insert some elements into the circular buffer.
      cb.push_back(1);
      cb.push_back(2);
      // Assertions to check push_backs have expected effect.
      assert(cb[0] == 1);
      assert(cb[1] == 2);
      assert(!cb.full());
      assert(cb.size() == 2);
      assert(cb.capacity() == 3);
      // Insert some other elements.
      cb.push_back(3);
      cb.push_back(4);
      // Evaluate the sum of all elements.
      int sum = std::accumulate(cb.begin(), cb.end(), 0);
      // Assertions to check state.
      assert(sum == 9);
      assert(cb[0] == 2);
      assert(cb[1] == 3);
      assert(cb[2] == 4);
      assert(*cb.begin() == 2);
      assert(cb.front() == 2);
      assert(cb.back() == 4);
      assert(cb.full());
      assert(cb.size() == 3);
      assert(cb.capacity() == 3);
      return 0;
   }
   //] [/circular_buffer_sum_example_1]
   /*
   There is no output from this example.
   */