foo.c: In function 'main':
foo.c:5:14: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    5 |  int n1, n2; scanf("%d%d", &n1, &n2);
      |              ^~~~~~~~~~~~~~~~~~~~~~~
foo.c:8:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    8 |   scanf("%d", &a1[i]);
      |   ^~~~~~~~~~~~~~~~~~~
foo.c:11:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   11 |   scanf("%d", &a2[i]);
      |   ^~~~~~~~~~~~~~~~~~~

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