In file included from /in/Compile/check.cpp:7:
/in/sokoban.hpp:270:13: error: implicit conversion changes signedness: 'int' to 'std::vector::size_type' (aka 'unsigned long') [-Werror,-Wsign-conversion]
    visited[px][py] = true;
    ~~~~~~~ ^~
/in/sokoban.hpp:270:17: error: implicit conversion changes signedness: 'int' to 'std::vector<bool, type-parameter-0-0>::size_type' (aka 'unsigned long') [-Werror,-Wsign-conversion]
    visited[px][py] = true;
    ~~~~~~~     ^~
/in/sokoban.hpp:284:17: error: use of undeclared identifier 'is_valid'
            if (is_valid(nx, ny, rows, cols, grid) && !visited[nx][ny]) {
                ^
/in/sokoban.hpp:286:25: error: implicit conversion changes signedness: 'int' to 'std::vector::size_type' (aka 'unsigned long') [-Werror,-Wsign-conversion]
                visited[nx][ny] = true;
                ~~~~~~~ ^~
/in/sokoban.hpp:286:29: error: implicit conversion changes signedness: 'int' to 'std::vector<bool, type-parameter-0-0>::size_type' (aka 'unsigned long') [-Werror,-Wsign-conversion]
                visited[nx][ny] = true;
                ~~~~~~~     ^~
/in/sokoban.hpp:307:26: error: implicit conversion changes signedness: 'int' to 'std::vector::size_type' (aka 'unsigned long') [-Werror,-Wsign-conversion]
            if (!visited[bx][by] && !target_bitmask.test(i)) {
                 ~~~~~~~ ^~
/in/sokoban.hpp:307:30: error: implicit conversion changes signedness: 'int' to 'std::vector<bool, type-parameter-0-0>::size_type' (aka 'unsigned long') [-Werror,-Wsign-conversion]
            if (!visited[bx][by] && !target_bitmask.test(i)) {
                 ~~~~~~~     ^~
7 errors generated.
/in/Compile/Makefile:16: recipe for target 'main' failed
make: *** [main] Error 1