ceph/src/boost/libs/sort/example/charstringsample.cpp

   1 // Example of sorting structs with a string key and indexing functors.
   2 //
   3 //  Copyright Steven Ross 2009-2014.
   4 //
   5 // Distributed under the Boost Software License, Version 1.0.
   6 //    (See accompanying file LICENSE_1_0.txt or copy at
   7 //          http://www.boost.org/LICENSE_1_0.txt)
   8
   9 //  See http://www.boost.org/libs/sort for library home page.
  10
  11 #include <boost/sort/spreadsort/string_sort.hpp>
  12 #include <time.h>
  13 #include <stdio.h>
  14 #include <stdlib.h>
  15 #include <algorithm>
  16 #include <vector>
  17 #include <iostream>
  18 #include <fstream>
  19 #include <string>
  20 using std::string;
  21 using namespace boost::sort::spreadsort;
  22
  23 struct DATA_TYPE {
  24     string a;
  25     inline bool operator<(const DATA_TYPE &y) const { return a < y.a;}
  26 };
  27
  28
  29 struct bracket {
  30   inline unsigned char operator()(const DATA_TYPE &x, size_t offset) const {
  31     return x.a[offset];
  32   }
  33 };
  34
  35 struct getsize {
  36   inline size_t operator()(const DATA_TYPE &x) const{ return x.a.size(); }
  37 };
  38
  39
  40
  41 //Pass in an argument to test std::sort
  42 int main(int argc, const char ** argv) {
  43   std::ifstream indata;
  44   bool stdSort = false;
  45   unsigned loopCount = 1;
  46   for (int u = 1; u < argc; ++u) {
  47     if (std::string(argv[u]) == "-std")
  48       stdSort = true;
  49     else
  50       loopCount = atoi(argv[u]);
  51   }
  52   double total = 0.0;
  53   //Run multiple loops, if requested
  54   std::vector<DATA_TYPE> array;
  55   for (unsigned u = 0; u < loopCount; ++u) {
  56     indata.open("input.txt", std::ios_base::in | std::ios_base::binary);
  57     if (indata.bad()) {
  58       printf("input.txt could not be opened\n");
  59       return 1;
  60     }
  61     DATA_TYPE inval;
  62     indata >> inval.a;
  63     while (!indata.eof() ) {
  64       array.push_back(inval);
  65       indata >> inval.a;
  66     }
  67
  68     indata.close();
  69     clock_t start, end;
  70     double elapsed;
  71     start = clock();
  72     if (stdSort) {
  73       std::sort(array.begin(), array.end());
  74     } else {
  75 //[bracket_1
  76       string_sort(array.begin(), array.end(), bracket(), getsize());
  77 //] [/bracket_1]
  78     }
  79     end = clock();
  80     elapsed = static_cast<double>(end - start);
  81     std::ofstream ofile;
  82     if (stdSort)
  83       ofile.open("standard_sort_out.txt", std::ios_base::out |
  84                  std::ios_base::binary | std::ios_base::trunc);
  85     else
  86       ofile.open("boost_sort_out.txt", std::ios_base::out |
  87                  std::ios_base::binary | std::ios_base::trunc);
  88     if (ofile.good()) {
  89       for (unsigned u = 0; u < array.size(); ++u)
  90         ofile << array[u].a << "\n";
  91       ofile.close();
  92     }
  93     total += elapsed;
  94     array.clear();
  95   }
  96   if (stdSort)
  97     printf("std::sort elapsed time %f\n", total / CLOCKS_PER_SEC);
  98   else
  99     printf("spreadsort elapsed time %f\n", total / CLOCKS_PER_SEC);
 100   return 0;
 101 }