foo.c: In function 'main':
foo.c:26:23: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   26 |    if(y%400==0||y%4==0&&y%100!=0)
      |                 ~~~~~~^~~~~~~~~~
foo.c:5:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    5 |  scanf("%d %d",&y,&m);
      |  ^~~~~~~~~~~~~~~~~~~~

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