foo.c: In function 'main':
foo.c:8:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    8 |  scanf("%d",&n1);
      |  ^~~~~~~~~~~~~~~
foo.c:9:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    9 |  scanf("%d",&n2);
      |  ^~~~~~~~~~~~~~~
foo.c: In function 'input':
foo.c:22:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   22 |  scanf("%d",&a[i]);
      |  ^~~~~~~~~~~~~~~~~

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