foo.c: In function 'main':
foo.c:4:5: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    4 |     scanf("%d",&n);
      |     ^~~~~~~~~~~~~~
foo.c:6:9: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    6 |         scanf("%d",&a[i]);
      |         ^~~~~~~~~~~~~~~~~

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