Compilare: main.cpp: In function 'int main()': main.cpp:41:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 41 | for (int j=0; j<s.size(); ++j) { | ~^~~~~~~~~ main.cpp:80:29: warning: 'yp' may be used uninitialized [-Wmaybe-uninitialized] 80 | g << xp << ' ' << yp << ' ' << ma_srf; | ^~~ main.cpp:66:13: note: 'yp' was declared here 66 | int xp, yp, ma_srf = 0; | ^~ main.cpp:80:16: warning: 'xp' may be used uninitialized [-Wmaybe-uninitialized] 80 | g << xp << ' ' << yp << ' ' << ma_srf; | ^~~ main.cpp:66:9: note: 'xp' was declared here 66 | int xp, yp, ma_srf = 0; | ^~