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For practice purpose, I wrote bubble sort in C++ two styles: C-ish and modern C++ compliant. I would like to have your comments on any point on these implementations.

Sorting.h
#ifndef SORTING_ALGORITHMS_H
#define SORTING_ALGORITHMS_H

#include <utility>
#include <vector>
//#include <iterator>
#include <algorithm>

namespace etpc
{
    template <class T>
    void sortBubble(T* pArrHead, std::size_t sArrSize)
    {
        for(std::size_t i=0; i<sArrSize-1; i++)
        {
            for(std::size_t j=0; j<sArrSize-i-1; j++)
            {
                if(pArrHead[j]>pArrHead[j+1])
                    std::swap(pArrHead[j], pArrHead[j+1]);
            }
        }
    }

    // May 2, 2020
    // Based on the following link
    // https://rosettacode.org/wiki/Sorting_algorithms/Bubble_sort#C.2B.2B
    // typename vs class
    // https://stackoverflow.com/questions/2023977/difference-of-keywords-typename-and-class-in-templates
    template <class T>
    void sortBubble(std::vector<T>& vArrHead)
    {
        typename std::vector<T>::iterator begin = std::begin(vArrHead);
        typename std::vector<T>::iterator end = std::end(vArrHead);
        while (begin != end--) {
            for (auto it = begin; it != end; ++it) {
                if (*(it + 1) < *it) {
                    std::iter_swap(it, it + 1);
                }
            }
        }
    }
}
#endif // SORTING_ALGORITHMS_H
Main.cpp
#include "Sorting/include/Sorting.h"

#include <iostream>
#include <chrono>
#include <iterator>

int main()
{
    std::chrono::steady_clock::time_point begin;
    std::chrono::steady_clock::time_point end;
    std::ostream_iterator<int> out_it (std::cout,", ");

    static const int i32Size = 50;
    int arr[i32Size] = {7804, 50398, 14945, 1814, 51383, 63156, 8432, 58103, 28175, 4339, 8361, 37158, 1529, 43066, 62052, 9591, 13168, 332, 55913, 2418, 48066, 46504, 52922, 39523, 36653, 30402, 9373, 56202, 50539, 41187, 42606, 32278, 63902, 41668, 7505, 46534, 25846, 49739, 63411, 45933, 15042, 6544, 35718, 17035, 34647, 15212, 52690, 64299, 61535, 45071};
    begin = std::chrono::steady_clock::now();
    etpc::sortBubble<int>(arr, i32Size);
    end = std::chrono::steady_clock::now();
    std::cout << "Time difference impArray = " << std::chrono::duration_cast<std::chrono::nanoseconds>(end - begin).count() << "[ns]" << std::endl;
    std::copy(std::begin(arr), std::end(arr), out_it);
    std::cout << '\n';

    std::vector<int> v = {7804, 50398, 14945, 1814, 51383, 63156, 8432, 58103, 28175, 4339, 8361, 37158, 1529, 43066, 62052, 9591, 13168, 332, 55913, 2418, 48066, 46504, 52922, 39523, 36653, 30402, 9373, 56202, 50539, 41187, 42606, 32278, 63902, 41668, 7505, 46534, 25846, 49739, 63411, 45933, 15042, 6544, 35718, 17035, 34647, 15212, 52690, 64299, 61535, 45071};
    begin = std::chrono::steady_clock::now();
    etpc::sortBubble<int>(v);
    end = std::chrono::steady_clock::now();
    std::cout << "Time difference impVector = " << std::chrono::duration_cast<std::chrono::nanoseconds>(end - begin).count() << "[ns]" << std::endl;
    std::copy(std::begin(v), std::end(v), out_it);
    std::cout << '\n';

    return 0;
}
```
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  • \$\begingroup\$ You can still replace it +1 by std::next(it) \$\endgroup\$ – JVApen May 2 at 20:29
  • \$\begingroup\$ It's unclear to me what you are trying to get out of this review, can you elaborate? \$\endgroup\$ – JVApen May 2 at 20:34
  • \$\begingroup\$ For C-style implementation, coding practises, algorithm-specific recommendation or your personal comments. For modern C++ implementation, does it suit with modern C++, can it be improved etc? @JVApen \$\endgroup\$ – Erdem Tuna May 3 at 11:16
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As you're already working with iterators you might as well accept iterators as arguments instead of the std::vector (as all STL algorithms do). That way it will work with other containers as well, even with raw pointers.

The comparison can also be customized like in std::sort. Maybe the caller wants to sort in descending order or compare structures by some field.

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