Compilare: main.cpp: In member function 'size_t Solutuion::dfs(std::__cxx11::list<long unsigned int>&, size_t)': main.cpp:61:31: warning: comparison of integer expressions of different signedness: 'int' and 'size_t' {aka 'long unsigned int'} [-Wsign-compare] 61 | for (int i = 0; i < len; ++i) { | ~~^~~~~ In file included from /usr/include/c++/12.2.1/bits/stl_iterator.h:85, from /usr/include/c++/12.2.1/bits/stl_algobase.h:67, from /usr/include/c++/12.2.1/bits/specfun.h:45, from /usr/include/c++/12.2.1/cmath:1935, from /usr/include/c++/12.2.1/x86_64-pc-linux-gnu/bits/stdc++.h:41, from main.cpp:1: In function 'constexpr decltype (::new(void*(0)) _Tp) std::construct_at(_Tp*, _Args&& ...) [with _Tp = long unsigned int; _Args = {const long unsigned int&}]', inlined from 'static constexpr void std::allocator_traits<std::allocator<_CharT> >::construct(allocator_type&, _Up*, _Args&& ...) [with _Up = long unsigned int; _Args = {const long unsigned int&}; _Tp = std::_List_node<long unsigned int>]' at /usr/include/c++/12.2.1/bits/alloc_traits.h:518:21, inlined from 'std::__cxx11::list<_Tp, _Alloc>::_Node* std::__cxx11::list<_Tp, _Alloc>::_M_create_node(_Args&& ...) [with _Args = {const long unsigned int&}; _Tp = long unsigned int; _Alloc = std::allocator<long unsigned int>]' at /usr/include/c++/12.2.1/bits/stl_list.h:713:33, inlined from 'void std::__cxx11::list<_Tp, _Alloc>::_M_insert(iterator, _Args&& ...) [with _Args = {const long unsigned int&}; _Tp = long unsigned int; _Alloc = std::allocator<long unsigned int>]' at /usr/include/c++/12.2.1/bits/stl_list.h:2005:32, inlined from 'void std::__cxx11::list<_Tp, _Alloc>::push_back(const value_type&) [with _Tp = long unsigned int; _Alloc = std::allocator<long unsigned int>]' at /usr/include/c++/12.2.1/bits/stl_list.h:1306:24, inlined from 'std::vector<std::set<long unsigned int> > Solutuion::solve()' at main.cpp:98:24: /usr/include/c++/12.2.1/bits/stl_construct.h:97:14: warning: 'source' may be used uninitialized [-Wmaybe-uninitialized] 97 | { return ::new((void*)__location) _Tp(std::forward<_Args>(__args)...); } | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ main.cpp: In member function 'std::vector<std::set<long unsigned int> > Solutuion::solve()': main.cpp:86:16: note: 'source' was declared here 86 | size_t source; | ^~~~~~