Compilare: user.cpp: In function ‘int main()’: user.cpp:33: warning: format ‘%d’ expects type ‘int’, but argument 3 has type ‘long int’ user.cpp:16: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:17: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:19: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result