foo.c: In function 'main':
foo.c:13:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   13 |  scanf("%d",&n);
      |  ^~~~~~~~~~~~~~
foo.c:15:6: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   15 |      scanf("%d",&a[i]);
      |      ^~~~~~~~~~~~~~~~~
foo.c:17:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   17 |  scanf("%d",&x);
      |  ^~~~~~~~~~~~~~

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