foo.c: In function 'main':
foo.c:8:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    8 |  scanf("%d%d",&l,&m);
      |  ^~~~~~~~~~~~~~~~~~~
foo.c:11:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   11 |  scanf("%d%d",&x,&y);
      |  ^~~~~~~~~~~~~~~~~~~

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