SBU021BubleSort

#include <iostream>
#define OPTIMAL

int main()
{
    const int arrSize{ 10 };
    int arr[arrSize]{ 6,1,4,2,8,9,11,3,2,1 };
    //int arr[arrSize]{ 1,1,1,2,2,9,11,1,2,1 };
    //int arr[arrSize]{ 1,2,3,4,5,6,7,8,9,10 };
    //int arr[arrSize]{ 1,2,3,4,5,6,7,9,8,7 };
    //int arr[arrSize]{ 10,9,8,7,6,5,4,3,2,1 };
    //int arr[arrSize]{0};

    for (int i{ 0 }; i < arrSize; ++i) { std::cout << arr[i] << ' '; } std::cout << '\n';

    for (int head{ 0 }; head < arrSize; ++head)
    {
        for (int tail{ arrSize - 1 }; tail > head; --tail)
        {
#ifndef OPTIMAL
            if (arr[tail] < arr[tail - 1])
#else
            if (arr[tail] < arr[head])
#endif
            {
                int tmp{ arr[tail] };
#ifndef OPTIMAL
                arr[tail] = arr[tail - 1];
                arr[tail - 1] = tmp;
#else
                arr[tail] = arr[head];
                arr[head] = tmp;
#endif

                for (int i{ 0 }; i < arrSize; ++i) { std::cout << arr[i] << ' '; } std::cout << " head:" << head << '\n';
            }
        }

    }

    for (int i{ 0 }; i < arrSize; ++i) { std::cout << arr[i] << ' '; } std::cout << '\n';
}