foo.c: In function 'main':
foo.c:8:4: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    8 |    scanf("%d%d%d",&n1,&n2,&n3);
      |    ^~~~~~~~~~~~~~~~~~~~~~~~~~~
foo.c:11:7: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   11 |       scanf("%d",&a1[i]);
      |       ^~~~~~~~~~~~~~~~~~
foo.c:15:7: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   15 |       scanf("%d",&a2[i]);
      |       ^~~~~~~~~~~~~~~~~~
foo.c:19:7: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   19 |       scanf("%d",&a3[i]);
      |       ^~~~~~~~~~~~~~~~~~

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