foo.cc: In function 'void dfs(int, int, int, int)':
foo.cc:9:34: warning: suggest parentheses around arithmetic in operand of '^' [-Wparentheses]
    9 |  dfs(x + 1, y, 0, t == 2 ? t : t + dir ^ 0);
      |                                ~~^~~~~
foo.cc:10:34: warning: suggest parentheses around arithmetic in operand of '^' [-Wparentheses]
   10 |  dfs(x, y + 1, 1, t == 2 ? t : t + dir ^ 1);
      |                                ~~^~~~~

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