foo.c: In function 'input':
foo.c:5:9: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    5 |         scanf("%d",&a[i]);
      |         ^~~~~~~~~~~~~~~~~
foo.c: In function 'main':
foo.c:17:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   17 |  scanf("%d %d",&n1 ,&n2);
      |  ^~~~~~~~~~~~~~~~~~~~~~~

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