Compilare: user.cpp:2:15: warning: ISO C++ forbids declaration of ‘main’ with no type [-Wreturn-type] main(int64_t N){std::ifstream("fetite.in")>>N;std::ofstream("fetite.out")<<(N-(1<<63-__builtin_clzll(N)))*2+1;} ^ user.cpp:2:1: warning: first argument of ‘int main(int64_t)’ should be ‘int’ [-Wmain] main(int64_t N){std::ifstream("fetite.in")>>N;std::ofstream("fetite.out")<<(N-(1<<63-__builtin_clzll(N)))*2+1;} ^~~~ user.cpp:2:1: warning: ‘int main(int64_t)’ takes only zero or two arguments [-Wmain] user.cpp: In function ‘int main(int64_t)’: user.cpp:2:85: warning: suggest parentheses around ‘-’ inside ‘<<’ [-Wparentheses] main(int64_t N){std::ifstream("fetite.in")>>N;std::ofstream("fetite.out")<<(N-(1<<63-__builtin_clzll(N)))*2+1;} ~~^~~~~~~~~~~~~~~~~~~