foo.cc: In function 'int main()':
foo.cc:20:14: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   20 |   if(sy%4==0 && sy%100!=0 || sy%400==0)
      |      ~~~~~~~~^~~~~~~~~~~~
foo.cc:46:14: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   46 |    if(i%4==0 && i%100!=0 || i%400==0)
      |       ~~~~~~~^~~~~~~~~~~
foo.cc:55:14: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   55 |   if(sy%4==0 && sy%100!=0 || sy%400==0)
      |      ~~~~~~~~^~~~~~~~~~~~
foo.cc:64:14: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   64 |   if(ey%4==0 && ey%100!=0 || ey%400==0)
      |      ~~~~~~~~^~~~~~~~~~~~

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