foo.cc: In function 'int BFS(Point)':
foo.cc:28:109: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   28 |    if (next.pos >= 0 && next.pos < len && a[next.pos] != ' ' && !vis[next.pos][next.x] && (i != 3 || i == 3 && now.x))
      |                                                                                                      ~~~~~~~^~~~~~~~

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