foo.cc: In function 'int main()':
foo.cc:6:11: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
    6 |  if(y%4==0&&y%100!=0||y%400==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);
      |  ~~~~~^~~~~~~~~~~~~~~

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