foo.cc: In function 'int main()':
foo.cc:6:17: warning: right operand of comma operator has no effect [-Wunused-value]
    6 |         cin>>a,b;
      |                 ^
foo.cc:17:37: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   17 |                 if(a%400==0||a%4==0 && a%100!=0)
      |                              ~~~~~~~^~~~~~~~~~~
foo.cc:5:15: warning: 'b' is used uninitialized [-Wuninitialized]
    5 |         int a,b;
      |               ^

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