PracticeDev/study_cpp/hash_table_test/hash_example_1.cpp

#include <iostream>
#include <map>
#include <string>

#ifdef __GNUC__
#include <ext/hash_map>
#else
#include <hash_map>
#endif

#ifdef __GXX_EXPERIMENTAL_CXX0X__
#include <unordered_map>
#endif

namespace std
{
    using namespace __gnu_cxx;
}

namespace __gnu_cxx
{
    template<> struct hash< std::string >
    {
        size_t operator()( const std::string& x ) const
        {
            return hash< const char* >()(x.c_str());
        }
    };
}

int main()
{
    std::map<std::string, std::string> stdMap;
    stdMap["_GLIBCXX_STD"] = "std";
    stdMap["_GLIBCXX_BEGIN_NESTED_NAMESPACE"] = "+namespace";
    stdMap["_GLIBCXX_BEGIN_NAMESPACE"] = "+namespace";
    stdMap["_GLIBCXX_END_NESTED_NAMESPACE"] = "}";
    stdMap["_GLIBCXX_END_NAMESPACE"] = "}";
    stdMap["_GLIBCXX_END_NAMESPACE_TR1"] = "}";
    stdMap["_GLIBCXX_BEGIN_NAMESPACE_TR1"] = "-namespace tr1 {";
    stdMap["_GLIBCXX_STD2"] = "2std";
    stdMap["_GLIBCXX_BEGIN_NESTED_NAMESPACE2"] = "2+namespace";
    stdMap["_GLIBCXX_BEGIN_NAMESPACE2"] = "2+namespace";
    stdMap["_GLIBCXX_END_NESTED_NAMESPACE2"] = "2}";
    stdMap["_GLIBCXX_END_NAMESPACE2"] = "2}";
    stdMap["_GLIBCXX_END_NAMESPACE_TR12"] = "2}";
    stdMap["_GLIBCXX_BEGIN_NAMESPACE_TR12"] = "2-namespace tr1 {";
    stdMap["_XXGLIBCXX_END_NAMESPACE_TR12"] = "X2}";
    stdMap["_XXGLIBCXX_BEGIN_NAMESPACE_TR12"] = "X2-namespace tr1 {";

    std::hash_map<std::string, std::string> hashMap;
    hashMap["_GLIBCXX_STD"] = "std";
    hashMap["_GLIBCXX_BEGIN_NESTED_NAMESPACE"] = "+namespace";
    hashMap["_GLIBCXX_BEGIN_NAMESPACE"] = "+namespace";
    hashMap["_GLIBCXX_END_NESTED_NAMESPACE"] = "}";
    hashMap["_GLIBCXX_END_NAMESPACE"] = "}";
    hashMap["_GLIBCXX_END_NAMESPACE_TR1"] = "}";
    hashMap["_GLIBCXX_BEGIN_NAMESPACE_TR1"] = "-namespace tr1 {";
    hashMap["_GLIBCXX_STD2"] = "2std";
    hashMap["_GLIBCXX_BEGIN_NESTED_NAMESPACE2"] = "2+namespace";
    hashMap["_GLIBCXX_BEGIN_NAMESPACE2"] = "2+namespace";
    hashMap["_GLIBCXX_END_NESTED_NAMESPACE2"] = "2}";
    hashMap["_GLIBCXX_END_NAMESPACE2"] = "2}";
    hashMap["_GLIBCXX_END_NAMESPACE_TR12"] = "2}";
    hashMap["_GLIBCXX_BEGIN_NAMESPACE_TR12"] = "2-namespace tr1 {";
    hashMap["_XXGLIBCXX_END_NAMESPACE_TR12"] = "X2}";
    hashMap["_XXGLIBCXX_BEGIN_NAMESPACE_TR12"] = "X2-namespace tr1 {";

#ifdef __GXX_EXPERIMENTAL_CXX0X__
    std::unordered_map<std::string, std::string> unorderedMap;
    unorderedMap["_GLIBCXX_STD"] = "std";
    unorderedMap["_GLIBCXX_BEGIN_NESTED_NAMESPACE"] = "+namespace";
    unorderedMap["_GLIBCXX_BEGIN_NAMESPACE"] = "+namespace";
    unorderedMap["_GLIBCXX_END_NESTED_NAMESPACE"] = "}";
    unorderedMap["_GLIBCXX_END_NAMESPACE"] = "}";
    unorderedMap["_GLIBCXX_END_NAMESPACE_TR1"] = "}";
    unorderedMap["_GLIBCXX_BEGIN_NAMESPACE_TR1"] = "-namespace tr1 {";
    unorderedMap["_GLIBCXX_STD2"] = "2std";
    unorderedMap["_GLIBCXX_BEGIN_NESTED_NAMESPACE2"] = "2+namespace";
    unorderedMap["_GLIBCXX_BEGIN_NAMESPACE2"] = "2+namespace";
    unorderedMap["_GLIBCXX_END_NESTED_NAMESPACE2"] = "2}";
    unorderedMap["_GLIBCXX_END_NAMESPACE2"] = "2}";
    unorderedMap["_GLIBCXX_END_NAMESPACE_TR12"] = "2}";
    unorderedMap["_GLIBCXX_BEGIN_NAMESPACE_TR12"] = "2-namespace tr1 {";
    unorderedMap["_XXGLIBCXX_END_NAMESPACE_TR12"] = "X2}";
    unorderedMap["_XXGLIBCXX_BEGIN_NAMESPACE_TR12"] = "X2-namespace tr1 {";
#endif

    for (int i = 0; i < 5; ++i)
    {
        const clock_t t = clock();
        for (int j = 0; j < 1000000; ++j) stdMap.find("testfindkey");
        std::cout << "stdMap " << i + 1 << " : " << clock() - t << std::endl;
    }

    std::cout << "/n---------------/n" << std::endl;

    for (int i = 0; i < 5; ++i)
    {
        const clock_t t = clock();
        for (int j = 0; j < 1000000; ++j) hashMap.find("testfindkey");
        std::cout << "hashMap " << i + 1 << " : " << clock() - t << std::endl;
    }

#ifdef __GXX_EXPERIMENTAL_CXX0X__
    std::cout << "/n---------------/n" << std::endl;

    for (int i = 0; i < 5; ++i)
    {
        const clock_t t = clock();
        for (int j = 0; j < 1000000; ++j) unorderedMap.find("testfindkey");
        std::cout << "unorderedMap " << i + 1 << " : " << clock() - t << std::endl;
    }
#endif

    return 0;
}