islands.cpp: In function 'std::variant<bool, std::vector<int, std::allocator<int> > > find_journey(int, int, std::vector<int>, std::vector<int>)':
islands.cpp:28:12: warning: 's_out' may be used uninitialized in this function [-Wmaybe-uninitialized]
28 | for (int i = s_out + 1; i < M; i++)
| ^
islands.cpp:43:74: warning: 'e_in' may be used uninitialized in this function [-Wmaybe-uninitialized]
43 | return vector<int>({s_out, s_in, e_out, e_in, s_in, s_out, e_in, e_out});
| ^
islands.cpp:43:74: warning: 'e_out' may be used uninitialized in this function [-Wmaybe-uninitialized]
islands.cpp:43:74: warning: 's_in' may be used uninitialized in this function [-Wmaybe-uninitialized]