message.cpp: In function 'int cycle(int, int)':
message.cpp:31:5: error: 'vis' was not declared in this scope
31 | vis[u] = 1;
| ^~~
message.cpp: In function 'std::vector<bool> receive_message(std::vector<std::vector<bool> >)':
message.cpp:50:8: error: request for member 'push_back' in 'g[j]', which is of non-class type 'int'
50 | g[j].push_back(d[j]);
| ^~~~~~~~~
message.cpp:51:11: error: request for member 'push_back' in 'g[d[j]]', which is of non-class type 'int'
51 | g[d[j]].push_back(j);
| ^~~~~~~~~
message.cpp:56:46: error: 'vis' was not declared in this scope
56 | for (int i = 0, p = 0; i < 31; ++i) if (!vis[i] && cycle(i, i)) {
| ^~~
message.cpp:74:19: error: cannot bind non-const lvalue reference of type 'int&' to an rvalue of type 'int'
74 | for (int &x : M) x = buf[z++];
| ^
In file included from /usr/include/c++/10/vector:68,
from message.h:1,
from message.cpp:1:
/usr/include/c++/10/bits/stl_bvector.h:86:5: note: after user-defined conversion: 'std::_Bit_reference::operator bool() const'
86 | operator bool() const _GLIBCXX_NOEXCEPT
| ^~~~~~~~