-// a sorting example that uses the worst-case distribution for spreadsort.
-//
-// 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;
-using namespace std;
-
-#define DATA_TYPE boost::uint64_t
-
-#define ALR_THRESHOLD 3
-
-const unsigned max_count = ALR_THRESHOLD - 1;
-const unsigned bit_shift = detail::rough_log_2_size(max_count) -
- detail::int_log_mean_bin_size;
-const unsigned radix_threshold = detail::rough_log_2_size(max_count) + 1;
-
-const DATA_TYPE typed_one = 1;
-
-void
-fill_vector(vector<DATA_TYPE> & input, const DATA_TYPE base_value,
- unsigned remaining_bits, const vector<unsigned> & indices,
- int index)
-{
- if (index < 0) {
- for (unsigned u = 0; u < max_count; ++u)
- input.push_back((base_value << remaining_bits) +
- (rand() % (1 << remaining_bits)));
- }
- else {
- unsigned shift = indices[index];
- fill_vector(input, (base_value << shift) + ((1 << shift) - 1),
- remaining_bits - shift, indices, index - 1);
- fill_vector(input, base_value << shift, remaining_bits - shift, indices,
- index - 1);
- }
-}
-
-//Generates a random index from 0 up to but not including count.
-unsigned
-get_index(unsigned count)
-{
- unsigned result = unsigned((rand() % (1 << 16))*uint64_t(count)/(1 << 16));
- if (result >= count)
- return count - 1;
- return result;
-}
-
-//Tests std::sort vs boost::sort::spreadsort on boost::sort's worst distribution.
-int main(int, const char **) {
- unsigned total_length = sizeof(DATA_TYPE) * 8;
- double std_sort_time = 0;
- double spreadsort_time = 0;
- for (int repetition = 0; repetition < 10; ++repetition) {
- vector<DATA_TYPE> input;
- vector<unsigned> offsets;
- unsigned bit_length = total_length - radix_threshold;
- unsigned bit_offset = bit_shift;
- for (; bit_length >= ++bit_offset; bit_length -= bit_offset)
- offsets.push_back(bit_offset);
- for (int ii = (1 << bit_length) - 1; ii >= 0; --ii)
- fill_vector(input, ii, total_length - bit_length,
- offsets, offsets.size() - 1);
-
- //Randomize the inputs slightly so they aren't in reverse-sorted order, for
- //which std::sort is very fast.
- for (unsigned u = 0; u < input.size() / 10; ++u)
- std::swap(input[get_index(input.size())], input[get_index(input.size())]);
-
- //Run both std::sort and boost::sort::spreadsort.
- for (unsigned u = 0; u < 2; ++u) {
- vector<DATA_TYPE> array = input;
- clock_t start, end;
- double elapsed;
- start = clock();
- if (u)
- std::sort(array.begin(), array.end());
- else
- boost::sort::spreadsort::spreadsort(array.begin(), array.end());
- end = clock();
- elapsed = static_cast<double>(end - start);
- if (u)
- std_sort_time += elapsed / CLOCKS_PER_SEC;
- else
- spreadsort_time += elapsed / CLOCKS_PER_SEC;
- array.clear();
- }
- }
-
- printf("std::sort elapsed time %f\n", std_sort_time);
- printf("spreadsort elapsed time %f\n", spreadsort_time);
- return 0;
-}
+// a sorting example that uses the worst-case distribution for spreadsort.\r
+//\r
+// Copyright Steven Ross 2009-2014.\r
+//\r
+// Distributed under the Boost Software License, Version 1.0.\r
+// (See accompanying file LICENSE_1_0.txt or copy at\r
+// http://www.boost.org/LICENSE_1_0.txt)\r
+\r
+// See http://www.boost.org/libs/sort for library home page.\r
+\r
+#include <boost/sort/spreadsort/spreadsort.hpp>\r
+#include <time.h>\r
+#include <stdio.h>\r
+#include <stdlib.h>\r
+#include <algorithm>\r
+#include <vector>\r
+#include <string>\r
+#include <fstream>\r
+#include <sstream>\r
+#include <iostream>\r
+using namespace boost::sort::spreadsort;\r
+using namespace std;\r
+\r
+#define DATA_TYPE boost::uint64_t\r
+\r
+#define ALR_THRESHOLD 3\r
+\r
+const unsigned max_count = ALR_THRESHOLD - 1;\r
+const unsigned bit_shift = detail::rough_log_2_size(max_count) -\r
+ detail::int_log_mean_bin_size;\r
+const unsigned radix_threshold = detail::rough_log_2_size(max_count) + 1;\r
+\r
+const DATA_TYPE typed_one = 1;\r
+\r
+void\r
+fill_vector(vector<DATA_TYPE> & input, const DATA_TYPE base_value,\r
+ unsigned remaining_bits, const vector<unsigned> & indices,\r
+ int index)\r
+{\r
+ if (index < 0) {\r
+ for (unsigned u = 0; u < max_count; ++u)\r
+ input.push_back((base_value << remaining_bits) +\r
+ (rand() % (1 << remaining_bits)));\r
+ }\r
+ else {\r
+ unsigned shift = indices[index];\r
+ fill_vector(input, (base_value << shift) + ((1 << shift) - 1),\r
+ remaining_bits - shift, indices, index - 1);\r
+ fill_vector(input, base_value << shift, remaining_bits - shift, indices,\r
+ index - 1);\r
+ }\r
+}\r
+\r
+//Generates a random index from 0 up to but not including count.\r
+unsigned\r
+get_index(unsigned count)\r
+{\r
+ unsigned result = unsigned((rand() % (1 << 16))*uint64_t(count)/(1 << 16));\r
+ if (result >= count)\r
+ return count - 1;\r
+ return result;\r
+}\r
+\r
+//Tests std::sort vs boost::sort::spreadsort on boost::sort's worst distribution.\r
+int main(int, const char **) {\r
+ unsigned total_length = sizeof(DATA_TYPE) * 8;\r
+ double std_sort_time = 0;\r
+ double spreadsort_time = 0;\r
+ for (int repetition = 0; repetition < 10; ++repetition) {\r
+ vector<DATA_TYPE> input;\r
+ vector<unsigned> offsets;\r
+ unsigned bit_length = total_length - radix_threshold;\r
+ unsigned bit_offset = bit_shift;\r
+ for (; bit_length >= ++bit_offset; bit_length -= bit_offset)\r
+ offsets.push_back(bit_offset);\r
+ for (int ii = (1 << bit_length) - 1; ii >= 0; --ii)\r
+ fill_vector(input, ii, total_length - bit_length,\r
+ offsets, offsets.size() - 1);\r
+\r
+ //Randomize the inputs slightly so they aren't in reverse-sorted order, for\r
+ //which std::sort is very fast.\r
+ for (unsigned u = 0; u < input.size() / 10; ++u)\r
+ std::swap(input[get_index(input.size())], input[get_index(input.size())]);\r
+\r
+ //Run both std::sort and boost::sort::spreadsort.\r
+ for (unsigned u = 0; u < 2; ++u) {\r
+ vector<DATA_TYPE> array = input;\r
+ clock_t start, end;\r
+ double elapsed;\r
+ start = clock();\r
+ if (u)\r
+ std::sort(array.begin(), array.end());\r
+ else\r
+ boost::sort::spreadsort::spreadsort(array.begin(), array.end());\r
+ end = clock();\r
+ elapsed = static_cast<double>(end - start);\r
+ if (u)\r
+ std_sort_time += elapsed / CLOCKS_PER_SEC;\r
+ else\r
+ spreadsort_time += elapsed / CLOCKS_PER_SEC;\r
+ array.clear();\r
+ }\r
+ }\r
+\r
+ printf("std::sort elapsed time %f\n", std_sort_time);\r
+ printf("spreadsort elapsed time %f\n", spreadsort_time);\r
+ return 0;\r
+}\r
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