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diff --git a/src/boost/libs/histogram/examples/getting_started_listing_04.cpp b/src/boost/libs/histogram/examples/getting_started_listing_04.cpp
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+++ b/src/boost/libs/histogram/examples/getting_started_listing_04.cpp
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+// Copyright 2019 Hans Dembinski
+//
+// 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)
+
+// clang-format off
+
+//[ getting_started_listing_04
+
+#include <algorithm>           // std::max_element
+#include <boost/format.hpp>    // only needed for printing
+#include <boost/histogram.hpp> // make_histogram, integer, indexed
+#include <iostream>            // std::cout, std::endl
+#include <sstream>             // std::ostringstream
+
+int main() {
+  using namespace boost::histogram;
+  using namespace boost::histogram::literals;
+
+  /*
+    We make a 3d histogram for color values (r, g, b) in an image. We assume the values
+    are of type char. The value range then is [0, 256). The integer axis is perfect for
+    color values.
+  */
+  auto h = make_histogram(
+    axis::integer<>(0, 256, "r"),
+    axis::integer<>(0, 256, "g"),
+    axis::integer<>(0, 256, "b")
+  );
+
+  /*
+    We don't have real image data, so fill some fake data.
+  */
+  h(1, 2, 3);
+  h(1, 2, 3);
+  h(0, 1, 0);
+
+  /*
+    Now let's say we want to know which color is most common. We can use std::max_element
+    on an indexed range for that.
+  */
+  auto ind = indexed(h);
+  auto max_it = std::max_element(ind.begin(), ind.end());
+
+  /*
+    max_it is a special iterator to the histogram cell with the highest count.
+    This iterator allows one to access the cell value, bin indices, and bin values.
+    You need to twice dereference it to get to the cell value.
+  */
+  std::ostringstream os;
+  os << boost::format("count=%i rgb=(%i, %i, %i)")
+        % **max_it % max_it->bin(0_c) % max_it->bin(1) % max_it->bin(2);
+
+  std::cout << os.str() << std::endl;
+
+  assert(os.str() == "count=2 rgb=(1, 2, 3)");
+}
+
+//]