foo.c: In function 'main':
foo.c:21:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   21 |  scanf("%d %d %d",&n1,&n2,&n3);
      |  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
foo.c:23:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   23 |   scanf("%d",&a[i]);
      |   ^~~~~~~~~~~~~~~~~
foo.c:25:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   25 |   scanf("%d",&b[i]);
      |   ^~~~~~~~~~~~~~~~~
foo.c:27:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   27 |   scanf("%d",&c[i]);
      |   ^~~~~~~~~~~~~~~~~

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