foo.cc: In function 'int isLeapYear(int)':
foo.cc:5:11: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
    5 |  if(y%4==0&&y%100!=0||y%400==0)
      |     ~~~~~~^~~~~~~~~~
foo.cc: In function 'int main()':
foo.cc:29:15: warning: 'a' may be used uninitialized in this function [-Wmaybe-uninitialized]
   29 |  cout<<" "<<a+r;
      |               ^

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