foo.c: In function 'main':
foo.c:31:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   31 |   scanf("%d %d %d",&a1,&a2,&a3);
      |   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
foo.c:37:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   37 |   scanf("%d",&a[i]);
      |   ^~~~~~~~~~~~~~~~~
foo.c:41:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   41 |   scanf("%d",&b[i]);
      |   ^~~~~~~~~~~~~~~~~
foo.c:45:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   45 |   scanf("%d",&c[i]);
      |   ^~~~~~~~~~~~~~~~~

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