mars.cpp: In function 'std::vector<int> construct_permutation(long long int)':
mars.cpp:15:5: warning: unused variable 'imp' [-Wunused-variable]
15 | ll imp = k;
| ^~~
/usr/bin/ld: /tmp/ccM40f21.o: in function `main':
stub.cpp:(.text.startup+0x793): undefined reference to `process(std::vector<std::vector<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::allocator<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > > >, std::allocator<std::vector<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >, std::allocator<std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > > > > >, int, int, int, int)'
collect2: error: ld returned 1 exit status