/in/foo.cc:8:1: error: 'vector' does not name a type
    8 | vector<vector<int>> op;
      | ^~~~~~
/in/foo.cc: In function 'void init()':
/in/foo.cc:14:5: error: 'op' was not declared in this scope
   14 |     op.push_back({});
      |     ^~
/in/foo.cc: In function 'void solve(int)':
/in/foo.cc:37:34: error: 'op' was not declared in this scope
   37 |             g[i][j] = (g[i][j] + op[x][idx]) % 4;
      |                                  ^~
/in/foo.cc: In function 'void dfs(int, int*)':
/in/foo.cc:64:25: error: 'op' was not declared in this scope
   64 |     for (int i = 1; i < op.size(); i ++ ) {
      |                         ^~
/in/foo.cc: In function 'int main()':
/in/foo.cc:87:5: error: 'memset' was not declared in this scope
   87 |     memset(f, false, sizeof(f));
      |     ^~~~~~
/in/foo.cc:4:1: note: 'memset' is defined in header '<cstring>'; did you forget to '#include <cstring>'?
    3 | #include <iostream>
  +++ |+#include <cstring>
    4 |