foo.c: In function 'main':
foo.c:7:5: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    7 |     scanf("%d%d", &n1, &n2);
      |     ^~~~~~~~~~~~~~~~~~~~~~~
foo.c:9:9: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    9 |         scanf("%d", &a[i]);
      |         ^~~~~~~~~~~~~~~~~~
foo.c:11:9: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   11 |         scanf("%d", &b[i]);
      |         ^~~~~~~~~~~~~~~~~~

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