foo.c: In function 'main':
foo.c:7:10: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    7 |  int n1; scanf("%d", &n1);
      |          ^~~~~~~~~~~~~~~~
foo.c:8:10: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    8 |  int n2; scanf("%d", &n2);
      |          ^~~~~~~~~~~~~~~~
foo.c:10:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   10 |   scanf("%d", &a[i]);
      |   ^~~~~~~~~~~~~~~~~~
foo.c:12:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   12 |   scanf("%d", &b[j]);
      |   ^~~~~~~~~~~~~~~~~~

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