Compilare: user.cpp: In function ‘int cb(long long int, long long int)’: user.cpp:11: warning: unused variable ‘last’ user.cpp: In function ‘int main()’: user.cpp:81: warning: format ‘%d’ expects type ‘int’, but argument 2 has type ‘long long int’ user.cpp:31: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:34: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:41: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result user.cpp:67: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result