foo.cc: In function 'int main()':
foo.cc:13:27: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   13 |    if((y%400==0)||(y%4==0)&&(y%100!=0))
      |                   ~~~~~~~~^~~~~~~~~~~~
foo.cc:5:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    5 |  scanf("%d %d",&y,&m);
      |  ~~~~~^~~~~~~~~~~~~~~
foo.cc:20:10: warning: 'd' may be used uninitialized in this function [-Wmaybe-uninitialized]
   20 |    cout<<d<<endl;
      |          ^

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