Compilare: user.cpp: In function ‘int main()’: user.cpp:74: warning: unused variable ‘sx’ user.cpp:74: warning: unused variable ‘sy’ user.cpp:105: warning: unused variable ‘onl’ user.cpp:105: warning: unused variable ‘onc’ user.cpp:106: warning: unused variable ‘lin’ user.cpp:106: warning: unused variable ‘col’ user.cpp:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result