foo.c: In function 'main':
foo.c:28:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   28 |  scanf("%d",&n1);
      |  ^~~~~~~~~~~~~~~
foo.c:29:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   29 |  scanf("%d",&n2);
      |  ^~~~~~~~~~~~~~~
foo.c:32:22: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   32 |  for(i=0; i<n1; i++) scanf("%d",&a[i]);
      |                      ^~~~~~~~~~~~~~~~~
foo.c:33:22: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   33 |  for(i=0; i<n2; i++) scanf("%d",&b[i]);
      |                      ^~~~~~~~~~~~~~~~~

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