foo.cc: In function 'int main()':
foo.cc:14:29: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   14 |          if(a%400==0||a%4==0&&a%100!=0)
      |                       ~~~~~~^~~~~~~~~~
foo.cc:13:5: warning: suggest explicit braces to avoid ambiguous 'else' [-Wdangling-else]
   13 |   if(i==2)
      |     ^

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