foo.c: In function 'main':
foo.c:26:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   26 |  scanf("%d",&n);
      |  ^~~~~~~~~~~~~~
foo.c:29:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   29 |   scanf("%d%d",&a[i],&b[i]);
      |   ^~~~~~~~~~~~~~~~~~~~~~~~~

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