Compilare: user.cpp: In function ‘int main()’: 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 user.cpp: In function ‘unsigned int cmmdc(unsigned int, unsigned int)’: user.cpp:9: warning: control reaches end of non-void function