I tried your suggestion literally and got this response in the browser:
/tmp/ccKDTXpt.o: In function `main':
test.cpp:(.text+0xa): undefined reference to `std::cout'
test.cpp:(.text+0xf): undefined reference to `std::basic_ostream<char, std::char_traits<char> >& std::operator<< <std::char_traits<char> >(std::basic_ostream<char, std::char_traits<char> >&, char const*)'
test.cpp:(.text+0x19): undefined reference to `std::cout'
test.cpp:(.text+0x1e): undefined reference to `std::basic_ostream<char, std::char_traits<char> >& std::operator<< <std::char_traits<char> >(std::basic_ostream<char, std::char_traits<char> >&, char const*)'
test.cpp:(.text+0x28): undefined reference to `std::cout'
test.cpp:(.text+0x2d): undefined reference to `std::basic_ostream<char, std::char_traits<char> >& std::operator<< <std::char_traits<char> >(std::basic_ostream<char, std::char_traits<char> >&, char const*)'
test.cpp:(.text+0x37): undefined reference to `std::cout'
test.cpp:(.text+0x3c): undefined reference to `std::basic_ostream<char, std::char_traits<char> >& std::operator<< <std::char_traits<char> >(std::basic_ostream<char, std::char_traits<char> >&, char const*)'
test.cpp:(.text+0x46): undefined reference to `std::cout'
test.cpp:(.text+0x4b): undefined reference to `std::basic_ostream<char, std::char_traits<char> >& std::operator<< <std::char_traits<char> >(std::basic_ostream<char, std::char_traits<char> >&, char const*)'
test.cpp:(.text+0x55): undefined reference to `std::cout'
test.cpp:(.text+0x5a): undefined reference to `std::basic_ostream<char, std::char_traits<char> >& std::operator<< <std::char_traits<char> >(std::basic_ostream<char, std::char_traits<char> >&, char const*)'
test.cpp:(.text+0x64): undefined reference to `std::cout'
test.cpp:(.text+0x69): undefined reference to `std::basic_ostream<char, std::char_traits<char> >& std::operator<< <std::char_traits<char> >(std::basic_ostream<char, std::char_traits<char> >&, char const*)'
test.cpp:(.text+0x73): undefined reference to `std::cout'
test.cpp:(.text+0x78): undefined reference to `std::basic_ostream<char, std::char_traits<char> >& std::operator<< <std::char_traits<char> >(std::basic_ostream<char, std::char_traits<char> >&, char const*)'
test.cpp:(.text+0x82): undefined reference to `std::cout'
test.cpp:(.text+0x87): undefined reference to `std::basic_ostream<char, std::char_traits<char> >& std::operator<< <std::char_traits<char> >(std::basic_ostream<char, std::char_traits<char> >&, char const*)'
/tmp/ccKDTXpt.o: In function `__static_initialization_and_destruction_0(int, int)':
test.cpp:(.text+0xb5): undefined reference to `std::ios_base::Init::Init()'
test.cpp:(.text+0xc4): undefined reference to `std::ios_base::Init::~Init()'
collect2: error: ld returned 1 exit status
then i tried to use `/usr/bin/g++` and it worked great!
thank you for everything (to quote the dolphins=aliens from the "hitchhiker's guide to the galaxy", «thanks for all the fish!») I insisted a little because I had intuition that something was wrong and that it would be useful for you so we have the solution