按字母顺序对两对“std：:p air<fs：:p ath， fs：:p ath>”排序

问：

我对C++相当陌生，我有两个文件夹，文件数量相同。我想按字母顺序对两个文件夹进行排序，然后打印filneame对：

[folder_1/file1.txt, folder_2/different_file4.txt] 
[folder_1/file2.txt, folder_2/different_file9.txt] 
[folder_1/file3.txt, folder_2/different_file35.txt] 
...

这是我到目前为止编写的代码：

int main (int argc, char **argv)
{ 
    cout << "C++ version: " << __cplusplus << "\n"; 
    
    const fs::path path_1{ "/home/path_to_folder1" };
    const fs::path path_2{ "/home/path_to_folder2" };
    std::vector<std::pair<fs::path, fs::path>> v{};
    std::transform(fs::recursive_directory_iterator{ path_1 }, {}, fs::recursive_directory_iterator{ path_2 }, std::back_inserter(v), [](auto& entry1, auto& entry2) {         
        return std::pair<fs::path, fs::path>{ entry1.path(), entry2.path() };
    }
    );
    // TODO: I need to sort, since directory iteration is not ordered on some file systems
    cout << "\n" ; 
    std:sort(v.begin(), v.end(), [](auto &left, auto &right) {
    return left < right; // probably not needed for what I want (i.e., filenames sorted in alphabetical order) 
    cout << (left < right); // debug
    });
    for (auto& p : v)
    {
        std::cout << '[' << p.first << ", " << p.second << "]\n";
    }
}

我知道我需要使用该功能，但我似乎无法让它工作。std::sort

编辑：

预期输出：

["/home/datasets/folder_1/file1.txt", "/home/datasets/folder_2/file432.txt"]
["/home/datasets/folder_1/file2.txt", "/home/datasets/folder_2/file456.txt"]
["/home/datasets/folder_1/file3.txt", "/home/datasets/folder_2/file556.txt"]

实际输出：

["/home/datasets/folder_1/file1.txt", "/home/datasets/folder_2/file556.txt"]
["/home/datasets/folder_1/file2.txt", "/home/datasets/folder_2/file432.txt"]
["/home/datasets/folder_1/file3.txt", "/home/datasets/folder_2/file456.txt"]