foo.c: In function 'main':
foo.c:6:9: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    6 |  int n; scanf("%d", &n);
      |         ^~~~~~~~~~~~~~~
foo.c:9:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    9 |   scanf("%d", &a[i]);
      |   ^~~~~~~~~~~~~~~~~~
foo.c:11:9: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   11 |  int x; scanf("%d", &x);
      |         ^~~~~~~~~~~~~~~

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