Compilare: user.cpp: In function ‘int main()’: user.cpp:124: warning: format ‘%lu’ expects type ‘long unsigned int’, but argument 2 has type ‘size_t’ user.cpp:126: warning: format ‘%lu’ expects type ‘long unsigned int’, but argument 2 has type ‘size_t’ user.cpp:96: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:99: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result