Compilare: main.cpp: In function 'void backtrack(int, int, long long int&, long long int, long long int, long long int)': main.cpp:20:14: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 20 | if(pos+1 < fact.size()){ | ~~~~~~^~~~~~~~~~~~~ In file included from /usr/include/c++/12.2.1/istream:39, from /usr/include/c++/12.2.1/sstream:38, from /usr/include/c++/12.2.1/complex:45, from /usr/include/c++/12.2.1/ccomplex:39, from /usr/include/c++/12.2.1/x86_64-pc-linux-gnu/bits/stdc++.h:54, from main.cpp:1: In member function 'std::basic_ostream<_CharT, _Traits>::__ostream_type& std::basic_ostream<_CharT, _Traits>::operator<<(long long int) [with _CharT = char; _Traits = std::char_traits<char>]', inlined from 'int main()' at main.cpp:62:11: /usr/include/c++/12.2.1/ostream:202:25: warning: 'best' may be used uninitialized [-Wmaybe-uninitialized] 202 | { return _M_insert(__n); } | ~~~~~~~~~^~~~~ main.cpp: In function 'int main()': main.cpp:40:27: note: 'best' was declared here 40 | long long l=1,r=1,mid,best; | ^~~~