ch8_3.cc

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#include <algorithm>
#include <cstdlib> /* srand, rand */
#include <ctime>
#include <fstream>
#include <iostream>
#include <vector>
 
template <class T>
std::vector<T> operator+(const std::vector<T> &vec1, const std::vector<T> &vec2);
 
template <class T>
std::vector<T> operator*(const std::vector<T> &vec1, const std::vector<T> &vec2);
 
template <class T>
std::vector<T> operator-(const std::vector<T> &vec1, const std::vector<T> &vec2);
 
int main(int argc, char const *argv[])
{
    // time
    clock_t t = clock();
    time_t rawtime;
    struct tm *timeinfo;
 
    // 获取文件路径，参考：http://www.cplusplus.com/reference/string/string/find_last_of/
    const std::string full_path_exec{argv[0]};
    std::string::size_type found = full_path_exec.find_last_of("/\\", std::string::npos);
    const std::string exec_path = full_path_exec.substr(0, found);
    const std::string exec_filename = full_path_exec.substr(found + 1, std::string::npos);
    const std::string data_file_name("\\ch8_3.result");
 
    // 打开测试数据文件
    std::string data_file_full_path{exec_path + data_file_name}; // 数据文件的绝对地址
    std::ofstream fout(data_file_full_path.c_str(), std::ios_base::app);
    if (fout.fail())
    {
        std::cerr << "无写权限，测试数据文件生成失败！\n";
        system("pause");
        return false;
    }
 
    // output time information
    time(&rawtime);                 // Get the current calendar time
    timeinfo = localtime(&rawtime); // Convert time_t to tm as local time
    // printf("Current local time and date: %s\n", asctime(timeinfo)); // Convert tm structure to string
    std::cout << "\nCurrent local time and date: " << asctime(timeinfo) << '\n';
    fout << "\nCurrent local time and date: " << asctime(timeinfo) << '\n';
 
    // 开始测试
    try
    {
        std::vector<size_t> vec1, vec2, vec_union, vec_intersect, vec_diff;
 
        /* initialize random seed: */
        srand(time(NULL));
 
        /* generate secret number between low and high: */
        size_t low{10}, high{25}, num_of_points{16};
        size_t iSecret;
        for (size_t i = 0; i < num_of_points; ++i)
        {
            iSecret = low + (high - low + 1) * rand() / (RAND_MAX + 1);
            vec1.push_back(iSecret);
            iSecret = low + (high - low + 1) * rand() / (RAND_MAX + 1);
            vec2.push_back(iSecret);
        }
 
        // 对vec1, vec2排序，并去除重复元素
        std::vector<size_t>::iterator it;
 
        std::sort(vec1.begin(), vec1.end());
        it = std::unique(vec1.begin(), vec1.end());
        vec1.resize(std::distance(vec1.begin(), it));
 
        std::sort(vec2.begin(), vec2.end());
        it = std::unique(vec2.begin(), vec2.end());
        vec2.resize(std::distance(vec2.begin(), it));
 
        // 输出vec1, vec2的元素
        std::cout << "set1 has " << (vec1.size()) << " elements:\n";
        fout << "set1 has " << (vec1.size()) << " elements:\n";
        for (auto it = vec1.begin(); it != vec1.end(); ++it)
        {
            std::cout << *it << ", ";
            fout << *it << ", ";
        }
        std::cout << '\n';
        fout << '\n';
 
        std::cout << "set2 has " << (vec2.size()) << " elements:\n";
        fout << "set2 has " << (vec2.size()) << " elements:\n";
        for (auto it = vec2.begin(); it != vec2.end(); ++it)
        {
            std::cout << *it << ", ";
            fout << *it << ", ";
        }
        std::cout << '\n';
        fout << '\n';
 
        // 求并，交，差，打印结果
        vec_union = vec1 + vec2;
        std::cout << "The union has " << (vec_union.size()) << " elements:\n";
        fout << "The union has " << (vec_union.size()) << " elements:\n";
        for (auto it = vec_union.begin(); it != vec_union.end(); ++it)
        {
            std::cout << *it << ", ";
            fout << *it << ", ";
        }
        std::cout << '\n';
        fout << '\n';
 
        vec_intersect = vec1 * vec2;
        std::cout << "The intersection has " << (vec_intersect.size()) << " elements:\n";
        fout << "The intersection has " << (vec_intersect.size()) << " elements:\n";
        for (auto it = vec_intersect.begin(); it != vec_intersect.end(); ++it)
        {
            std::cout << *it << ", ";
            fout << *it << ", ";
        }
        std::cout << '\n';
        fout << '\n';
 
        vec_diff = vec1 - vec2;
        std::cout << "The difference has " << (vec_diff.size()) << " elements:\n";
        fout << "The difference has " << (vec_diff.size()) << " elements:\n";
        for (auto it = vec_diff.begin(); it != vec_diff.end(); ++it)
        {
            std::cout << *it << ", ";
            fout << *it << ", ";
        }
        std::cout << '\n';
        fout << '\n';
    }
    catch (const std::string &e)
    {
        std::cerr << e << '\n';
        fout << e << '\n';
    }
    catch (const std::exception &e)
    {
        std::cerr << e.what() << '\n';
        fout << e.what() << '\n';
    }
 
    // output time information
    t = clock() - t;
    // printf("\nIt took me %ld clicks (%f seconds).\n", t, ((float)t) / CLOCKS_PER_SEC);
    std::cout << "\nIt took me " << t << " clicks (" << ((float)t) / CLOCKS_PER_SEC << " seconds).\n";
    fout << "\nIt took me " << t << " clicks (" << ((float)t) / CLOCKS_PER_SEC << " seconds).\n";
 
    // 测试结束
    fout.close();
    system("pause");
    return 0;
} // main
 
template <class T>
std::vector<T> operator+(const std::vector<T> &vec1, const std::vector<T> &vec2)
{
    std::vector<T> vec_union(vec1.size() + vec2.size());
 
    auto first1{vec1.begin()}, last1{vec1.end()};
 
    auto first2{vec2.begin()}, last2{vec2.end()};
 
    auto result{vec_union.begin()};
 
    while (true)
    {
        if (first1 == last1)
        {
            result = std::copy(first2, last2, result);
            break;
        }
        if (first2 == last2)
        {
            result = std::copy(first1, last1, result);
            break;
        }
 
        if (*first1 < *first2)
        {
            *result = *first1;
            ++first1;
        }
        else if (*first2 < *first1)
        {
            *result = *first2;
            ++first2;
        }
        else
        {
            *result = *first1;
            ++first1;
            ++first2;
        }
        ++result;
    }
    vec_union.resize(result - vec_union.begin());
    return vec_union;
}
 
template <class T>
std::vector<T> operator*(const std::vector<T> &vec1, const std::vector<T> &vec2)
{
    std::vector<T> vec_intersect(vec1.size());
 
    auto first1{vec1.begin()}, last1{vec1.end()};
 
    auto first2{vec2.begin()}, last2{vec2.end()};
 
    auto result{vec_intersect.begin()};
 
    while (first1 != last1 && first2 != last2)
    {
        if (*first1 < *first2)
            ++first1;
        else if (*first2 < *first1)
            ++first2;
        else
        {
            *result = *first1;
            ++result;
            ++first1;
            ++first2;
        }
    }
    vec_intersect.resize(result - vec_intersect.begin());
    return vec_intersect;
}
 
template <class T>
std::vector<T> operator-(const std::vector<T> &vec1, const std::vector<T> &vec2)
{
    std::vector<T> vec_diff(vec1.size());
 
    auto first1{vec1.begin()}, last1{vec1.end()};
 
    auto first2{vec2.begin()}, last2{vec2.end()};
 
    auto result{vec_diff.begin()};
 
    while (first1 != last1 && first2 != last2)
    {
        if (*first1 < *first2)
        {
            *result = *first1;
            ++result;
            ++first1;
        }
        else if (*first2 < *first1)
            ++first2;
        else
        {
            ++first1;
            ++first2;
        }
    }
    result = std::copy(first1, last1, result);
    vec_diff.resize(result - vec_diff.begin());
    return vec_diff;
}