foo.cc: In function 'int main()':
foo.cc:26:34: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   26 |                         if(i%4==0&&i%100!=0||i%400==0)C+=366;
      |                            ~~~~~~^~~~~~~~~~
foo.cc:29:27: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   29 |                 if(sy%4==0&&sy%100!=0||sy%400==0) m[2]=29;
      |                    ~~~~~~~^~~~~~~~~~~
foo.cc:32:27: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   32 |                 if(ey%4==0&&ey%100!=0||ey%400==0) m[2]=29;
      |                    ~~~~~~~^~~~~~~~~~~

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