99 lines
2.8 KiB
C++
99 lines
2.8 KiB
C++
//! \brief Integer sort with a rightshift functor sorting example.
|
|
//! \file
|
|
//
|
|
// 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.
|
|
|
|
// Caution: this file contains Quickbook markup as well as code
|
|
// and comments, don't change any of the special comment markups!
|
|
|
|
#include <boost/sort/spreadsort/spreadsort.hpp>
|
|
#include <time.h>
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <algorithm>
|
|
#include <vector>
|
|
#include <string>
|
|
#include <fstream>
|
|
#include <iostream>
|
|
using namespace boost::sort::spreadsort;
|
|
|
|
#define DATA_TYPE int
|
|
|
|
//[rightshift_int_functor
|
|
struct rightshift {
|
|
inline int operator()(DATA_TYPE x, unsigned offset) { return x >> offset; }
|
|
};
|
|
//] [/rightshift_int_functor]
|
|
|
|
//Pass in an argument to test std::sort
|
|
int main(int argc, const char ** argv) {
|
|
size_t uCount,uSize=sizeof(DATA_TYPE);
|
|
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;
|
|
}
|
|
double total = 0.0;
|
|
std::vector<DATA_TYPE> array;
|
|
input.seekg (0, std::ios_base::end);
|
|
size_t length = input.tellg();
|
|
uCount = length/uSize;
|
|
//Run multiple loops, if requested
|
|
for (unsigned u = 0; u < loopCount; ++u) {
|
|
input.seekg (0, std::ios_base::beg);
|
|
//Conversion to a vector
|
|
array.resize(uCount);
|
|
unsigned v = 0;
|
|
while (input.good() && v < uCount)
|
|
input.read(reinterpret_cast<char *>(&(array[v++])), uSize );
|
|
if (v < uCount)
|
|
array.resize(v);
|
|
clock_t start, end;
|
|
double elapsed;
|
|
start = clock();
|
|
if (stdSort) {
|
|
std::sort(array.begin(), array.end());
|
|
} else {
|
|
//[rightshift_1
|
|
integer_sort(array.begin(), array.end(), rightshift());
|
|
//] [/rightshift_1]
|
|
}
|
|
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])), sizeof(array[v]) );
|
|
}
|
|
ofile.close();
|
|
}
|
|
total += elapsed;
|
|
array.clear();
|
|
}
|
|
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;
|
|
}
|