Compilare: user.cpp: In function ‘int main()’: user.cpp:51: warning: name lookup of ‘i’ changed user.cpp:11: warning: matches this ‘i’ under ISO standard rules user.cpp:28: warning: matches this ‘i’ under old rules user.cpp:15: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:16: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:18: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result