BR012cycleFrame

#include <iostream>
#include <chrono>
#include <thread>


/*
*******
*#####*
*#***#*
*#***#*
*#***#*
*#####*
*******
*/

int main()
{
    const char* CSI = "\033[";
    const char* CLRSCR = "2J";

    int side{15};
    int sub{ 1 };
    //std::cout << "enter line length\n";
    //std::cin >> side;
    const char pos = '#';
    const char neg = ' ';
    bool positive{ false };
    bool hPositive{ false };
    bool vPositive{ false };

    const int maxLoop{ 6 };
    const int minLoop{ 0 };

    int loop{ minLoop };
    int loopStep{ 1 };


    while (true)
    {
        if ((loop >= maxLoop and loopStep > 0) or (loop <= minLoop and loopStep < 0))
        {
            loopStep *= -1;
            std::cout << '\n';
        }

        sub = loop;

        for (int y{ 0 }; y < side; ++y)
        {
            for (int x{ 0 }; x < side; ++x)
            {
                hPositive = ((y == sub or y == (side - 1 - sub)) and (x >= sub and x <= (side - 1 - sub)));
                vPositive = ((x == sub or x == (side - 1 - sub)) and (y >= sub and y <= (side - 1 - sub)));
                positive = (hPositive or vPositive);

                std::cout << ' ' << (positive ? pos : neg) << ' ';
            }
            std::cout << '\n';
        }
        std::this_thread::sleep_for(std::chrono::milliseconds(1000)); //make some pause for better output look :)
        std::cout << CSI << CLRSCR; //portable clear screen

        loop += loopStep;
    }

    return 0;
}
//std::this_thread::sleep_for(std::chrono::milliseconds(200)); //make some pause for better output look :)
//const char* CSI = "\033[";
//std::cout << CSI << "2J"; //portable clear screen