SFML C++. Bouncing ball with showing coordinates

l use MinGW and lightweight editor VSCode: https://code.visualstudio.com/docs/languages/cpp​

Type the command: mingw32-make

Makefile

# -mwindows - without a console window

CC = g++

INC = -I"E:\Libs\SFML-2.5.1-windows-gcc-7.3.0-mingw-32-bit\include"

LIB = -L"E:\Libs\SFML-2.5.1-windows-gcc-7.3.0-mingw-32-bit\lib"

all: main.o
	$(CC) -mwindows main.o $(LIB) -lsfml-system -lsfml-window -lsfml-graphics -o app

main.o: main.cpp
	$(CC) -c $(INC) main.cpp

main.cpp

#include <iostream>
#include <sstream>
#include <SFML/Graphics.hpp>

template <typename T>
std::string to_string_with_presision(const T a_value, const int n = 1)
{
    std::ostringstream out;
    out.precision(n);
    out << std …