In file included from /in/Compile/check.cpp:7:
/in/sokoban.hpp:123:34: error: implicit conversion changes signedness: 'int' to 'unsigned long' [-Werror,-Wsign-conversion]
            if (board[position + pos[i][0]] == '#' || state.boxes[position + pos[i][0]] == 'B') {
                               ~ ^~~~~~~~~
/in/sokoban.hpp:123:78: error: implicit conversion changes signedness: 'int' to 'unsigned long' [-Werror,-Wsign-conversion]
            if (board[position + pos[i][0]] == '#' || state.boxes[position + pos[i][0]] == 'B') {
                                                                           ~ ^~~~~~~~~
/in/sokoban.hpp:126:34: error: implicit conversion changes signedness: 'int' to 'unsigned long' [-Werror,-Wsign-conversion]
            if (board[position + pos[i][1]] == '#' || state.boxes[position + pos[i][1]] == 'B') {
                               ~ ^~~~~~~~~
/in/sokoban.hpp:126:78: error: implicit conversion changes signedness: 'int' to 'unsigned long' [-Werror,-Wsign-conversion]
            if (board[position + pos[i][1]] == '#' || state.boxes[position + pos[i][1]] == 'B') {
                                                                           ~ ^~~~~~~~~
/in/sokoban.hpp:129:34: error: implicit conversion changes signedness: 'int' to 'unsigned long' [-Werror,-Wsign-conversion]
            if (board[position + pos[i][2]] == '#' || state.boxes[position + pos[i][2]] == 'B') {
                               ~ ^~~~~~~~~
/in/sokoban.hpp:129:78: error: implicit conversion changes signedness: 'int' to 'unsigned long' [-Werror,-Wsign-conversion]
            if (board[position + pos[i][2]] == '#' || state.boxes[position + pos[i][2]] == 'B') {
                                                                           ~ ^~~~~~~~~
/in/sokoban.hpp:142:38: error: implicit conversion changes signedness: 'int' to 'unsigned long' [-Werror,-Wsign-conversion]
    size_t next = state.player + dir.first * col + dir.second;
                                 ~~~~^~~~~ ~
/in/sokoban.hpp:142:56: error: implicit conversion changes signedness: 'int' to 'unsigned long' [-Werror,-Wsign-conversion]
    size_t next = state.player + dir.first * col + dir.second;
                                                 ~ ~~~~^~~~~~
/in/sokoban.hpp:143:34: error: implicit conversion changes signedness: 'int' to 'unsigned long' [-Werror,-Wsign-conversion]
    size_t nextnext = next + dir.first * col + dir.second;
                             ~~~~^~~~~ ~
/in/sokoban.hpp:143:52: error: implicit conversion changes signedness: 'int' to 'unsigned long' [-Werror,-Wsign-conversion]
    size_t nextnext = next + dir.first * col + dir.second;
                                             ~ ~~~~^~~~~~
/in/sokoban.hpp:156:38: error: implicit conversion changes signedness: 'int' to 'unsigned long' [-Werror,-Wsign-conversion]
    size_t next = state.player + dir.first * col + dir.second;
                                 ~~~~^~~~~ ~
/in/sokoban.hpp:156:56: error: implicit conversion changes signedness: 'int' to 'unsigned long' [-Werror,-Wsign-conversion]
    size_t next = state.player + dir.first * col + dir.second;
                                                 ~ ~~~~^~~~~~
/in/sokoban.hpp:158:38: error: implicit conversion changes signedness: 'int' to 'unsigned long' [-Werror,-Wsign-conversion]
        size_t nextnext = next + dir.first * col + dir.second;
                                 ~~~~^~~~~ ~
/in/sokoban.hpp:158:56: error: implicit conversion changes signedness: 'int' to 'unsigned long' [-Werror,-Wsign-conversion]
        size_t nextnext = next + dir.first * col + dir.second;
                                                 ~ ~~~~^~~~~~
/in/Compile/check.cpp:85:22: error: use of undeclared identifier 'print_answer'
        submit_ans = print_answer(index);
                     ^
15 errors generated.
/in/Compile/Makefile:16: recipe for target 'main' failed
make: *** [main] Error 1