Imported from /home/lorry/working-area/delta_boost-tarball/boost_1_58_0.tar.bz2.HEADboost_1_58_0master

1 files changed, 107 insertions, 0 deletions

diff --git a/libs/sort/example/keyplusdatasample.cpp b/libs/sort/example/keyplusdatasample.cpp
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+// spreadsort key and data sorting example.

+//

+//  Copyright Steven Ross 2009-2014.

+//

+// 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/sort for library home page.

+

+#include <boost/sort/spreadsort/spreadsort.hpp>

+#include <time.h>

+#include <stdio.h>

+#include <stdlib.h>

+#include <algorithm>

+#include <vector>

+#include <string>

+#include <fstream>

+#include <sstream>

+#include <iostream>

+using namespace boost::sort::spreadsort;

+

+struct DATA_TYPE {

+    int key;

+    std::string data;

+    };

+//functor example

+struct lessthan {

+  inline bool operator()(const DATA_TYPE &x, const DATA_TYPE &y) const {

+    return x.key < y.key;

+  }

+};

+

+struct rightshift {

+  inline int operator()(const DATA_TYPE &x, const unsigned offset) {

+    return x.key >> offset;

+  }

+};

+

+//Pass in an argument to test std::sort

+int main(int argc, const char ** argv) {

+  size_t uSize = sizeof(int);

+  bool stdSort = false;

+  unsigned loopCount = 1;

+  for (int u = 1; u < argc; ++u) {

+    if (std::string(argv[u]) == "-std")

+      stdSort = true;

+    else

+      loopCount = atoi(argv[u]);

+  }

+  std::ifstream input("input.txt", std::ios_base::in | std::ios_base::binary);

+  if (input.fail()) {

+    printf("input.txt could not be opened\n");

+    return 1;

+  }

+  input.seekg (0, std::ios_base::end);

+    size_t length = input.tellg();

+  double total = 0.0;

+  std::vector<DATA_TYPE> array;

+  array.reserve(length/uSize);

+  unsigned uCount = length/uSize;

+  //Run multiple loops, if requested

+  for (unsigned u = 0; u < loopCount; ++u) {

+    input.seekg (0, std::ios_base::beg);

+    unsigned v = 0;

+    while (input.good() && v++ < uCount) { // EOF or failure stops the reading

+     DATA_TYPE element;

+     input.read(reinterpret_cast<char *>(&(element.key)), sizeof(element.key));

+     std::stringstream intstr;

+         intstr << element.key;

+         element.data = intstr.str();

+         array.push_back(element);

+    }  

+    clock_t start, end;

+    double elapsed;

+    start = clock();

+    if (stdSort)

+      std::sort(array.begin(), array.end(), lessthan());

+    else

+      integer_sort(array.begin(), array.end(), rightshift(), lessthan());

+    end = clock();

+    elapsed = static_cast<double>(end - start) ;

+    std::ofstream ofile;

+    if (stdSort)

+      ofile.open("standard_sort_out.txt", std::ios_base::out |

+                 std::ios_base::binary | std::ios_base::trunc);

+    else

+      ofile.open("boost_sort_out.txt", std::ios_base::out |

+                 std::ios_base::binary | std::ios_base::trunc);

+    if (ofile.good()) {

+      for (unsigned v = 0; v < array.size(); ++v) {

+        ofile.write(reinterpret_cast<char *>(&(array[v].key)), 

+                    sizeof(array[v].key));

+        ofile << array[v].data;

+      }

+      ofile.close();

+    }

+    total += elapsed;

+    array.clear();

+  }

+  input.close();

+  if (stdSort)

+    printf("std::sort elapsed time %f\n", total / CLOCKS_PER_SEC);

+  else

+    printf("spreadsort elapsed time %f\n", total / CLOCKS_PER_SEC);

+  return 0;

+}