vision.cpp: In function 'void construct_network(int, int, int)':
vision.cpp:30:29: error: 'class std::vector<int>' has no member named 'pb'
vec.pb(q * W + z);
^~
vision.cpp:31:36: error: could not convert '((i * W) + j)' from 'int' to 'std::vector<int>'
add_and({add_and(i * W + j), add_and(vec)});
~~~~~~^~~
vision.cpp:31:55: error: could not convert '{<expression error>, add_and(std::vector<int>(vec))}' from '<brace-enclosed initializer list>' to 'std::vector<int>'
add_and({add_and(i * W + j), add_and(vec)});
^
vision.cpp:16:6: warning: unused variable 'fi' [-Wunused-variable]
int fi = H * W;
^~