foo.cc: In function 'int main()':
foo.cc:9:26: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
    9 |                 if(x%4==0&&x%100!=0||x%400==0)
      |                    ~~~~~~^~~~~~~~~~
foo.cc:11:20: warning: 'cnt' may be used uninitialized in this function [-Wmaybe-uninitialized]
   11 |                 cnt++;
      |                 ~~~^~

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