foo.c: In function 'main':
foo.c:25:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   25 |  scanf("%d",&n);
      |  ^~~~~~~~~~~~~~
foo.c:28:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   28 |   scanf("%d",&a[i]);
      |   ^~~~~~~~~~~~~~~~~
foo.c:30:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   30 |  scanf("%d",&s);
      |  ^~~~~~~~~~~~~~

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