foo.c: In function 'main':
foo.c:7:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    7 |   scanf("%d",&n);
      |   ^~~~~~~~~~~~~~
foo.c:9:4: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    9 |    scanf("%d",&a[i]);
      |    ^~~~~~~~~~~~~~~~~

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