1//! \brief spreadsort string functor sorting example.
2//! \file
3//
4// Copyright Steven Ross 2009-2014.
5//
6// Distributed under the Boost Software License, Version 1.0.
7// (See accompanying file LICENSE_1_0.txt or copy at
8// http://www.boost.org/LICENSE_1_0.txt)
9
10// See http://www.boost.org/libs/sort for library home page.
11
12// Caution: this file contains Quickbook markup as well as code
13// and comments, don't change any of the special comment markups!
14
15#include <boost/sort/spreadsort/string_sort.hpp>
16#include <time.h>
17#include <stdio.h>
18#include <stdlib.h>
19#include <algorithm>
20#include <vector>
21#include <iostream>
22#include <fstream>
23#include <string>
24using std::string;
25using namespace boost::sort::spreadsort;
26
27struct DATA_TYPE {
28 string a;
29};
30
31//[lessthan_functor
32
33struct lessthan {
34 inline bool operator()(const DATA_TYPE &x, const DATA_TYPE &y) const {
35 return x.a < y.a;
36 }
37};
38//] [/lessthan_functor]
39
40//[bracket_functor
41struct bracket {
42 inline unsigned char operator()(const DATA_TYPE &x, size_t offset) const {
43 return x.a[offset];
44 }
45};
46//] [/bracket_functor]
47
48//[getsize_functor
49struct getsize {
50 inline size_t operator()(const DATA_TYPE &x) const{ return x.a.size(); }
51};
52//] [/getsize_functor]
53
54//Pass in an argument to test std::sort
55int main(int argc, const char ** argv) {
56 std::ifstream indata;
57 std::ofstream outfile;
58 bool stdSort = false;
59 unsigned loopCount = 1;
60 for (int u = 1; u < argc; ++u) {
61 if (std::string(argv[u]) == "-std")
62 stdSort = true;
63 else
64 loopCount = atoi(nptr: argv[u]);
65 }
66 double total = 0.0;
67 //Run multiple loops, if requested
68 std::vector<DATA_TYPE> array;
69 for (unsigned u = 0; u < loopCount; ++u) {
70 indata.open(s: "input.txt", mode: std::ios_base::in | std::ios_base::binary);
71 if (indata.bad()) {
72 printf(format: "input.txt could not be opened\n");
73 return 1;
74 }
75 DATA_TYPE inval;
76 indata >> inval.a;
77 while (!indata.eof() ) {
78 array.push_back(x: inval);
79 //Inserting embedded nulls and empty strings
80 if (!(array.size() % 100)) {
81 if (inval.a.empty() || !(array.size() % 1000)) {
82 inval.a = "";
83 array.push_back(x: inval);
84 }
85 else {
86 inval.a[0] = '\0';
87 array.push_back(x: inval);
88 }
89 }
90 indata >> inval.a;
91 }
92
93 indata.close();
94 clock_t start, end;
95 double elapsed;
96 start = clock();
97 if (stdSort) {
98 std::sort(first: array.begin(), last: array.end(), comp: lessthan());
99 } else {
100//[stringsort_functors_call
101 string_sort(first: array.begin(), last: array.end(), get_character: bracket(), length: getsize(), comp: lessthan());
102//] [/stringsort_functors_call]
103 }
104 end = clock();
105 elapsed = static_cast<double>(end - start);
106 if (stdSort) {
107 outfile.open(s: "standard_sort_out.txt", mode: std::ios_base::out |
108 std::ios_base::binary | std::ios_base::trunc);
109 } else {
110 outfile.open(s: "boost_sort_out.txt", mode: std::ios_base::out |
111 std::ios_base::binary | std::ios_base::trunc);
112 }
113 if (outfile.good()) {
114 for (unsigned u = 0; u < array.size(); ++u)
115 outfile << array[u].a << "\n";
116 outfile.close();
117 }
118 total += elapsed;
119 array.clear();
120 }
121 if (stdSort) {
122 printf(format: "std::sort elapsed time %f\n", total / CLOCKS_PER_SEC);
123 } else {
124 printf(format: "spreadsort elapsed time %f\n", total / CLOCKS_PER_SEC);
125 }
126 return 0;
127}
128

source code of boost/libs/sort/example/stringfunctorsample.cpp