Compilare: user.cpp: In function ‘long long int calc(long long int)’: user.cpp:16: warning: no return statement in function returning non-void user.cpp: In function ‘int main()’: user.cpp:23: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:24: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:21: warning: ‘now’ may be used uninitialized in this function user.cpp:21: warning: ‘sol’ may be used uninitialized in this function