Compilare: user.cpp: In function ‘long long int exp(long long int, long long int)’: user.cpp:15:1: warning: control reaches end of non-void function [-Wreturn-type] } ^ user.cpp: In function ‘int main()’: user.cpp:40:14: warning: ‘n’ may be used uninitialized in this function [-Wmaybe-uninitialized] sol=phi(n); ^