Compilare: user.cpp: In function ‘int main()’: user.cpp:293: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:295: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:298: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:306: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result