foo.c: In function 'main':
foo.c:4:17: warning: unused variable 'day' [-Wunused-variable]
    4 |  int year,month,day;
      |                 ^~~
foo.c:5:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    5 |  scanf("%d %d",&year,&month);
      |  ^~~~~~~~~~~~~~~~~~~~~~~~~~~

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