Compilare: user.cpp: In function ‘int main()’: user.cpp:147:6: warning: unused variable ‘i’ [-Wunused-variable] int i, T; ^ user.cpp:138:50: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen((fileInput + ".in").c_str(), "r", stdin); ^ user.cpp:139:52: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen((fileInput + ".out").c_str(), "w", stdout); ^