In file included from /in/Compile/check.cpp:7:
/in/sokoban.hpp:63:16: error: use of undeclared identifier 'dead_ends'
               dead_ends |= (1ULL << pos);
               ^
/in/sokoban.hpp:116:21: error: use of undeclared identifier 'dead_ends'
                if (dead_ends & (1ULL << new_box_pos)) {
                    ^
2 errors generated.
/in/Compile/Makefile:16: recipe for target 'main' failed
make: *** [main] Error 1