foo.c: In function 'main':
foo.c:8:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    8 |  scanf("%d%d",&n1,&n2);
      |  ^~~~~~~~~~~~~~~~~~~~~
foo.c:11:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   11 |   scanf("%d",&a[i]);
      |   ^~~~~~~~~~~~~~~~~
foo.c:15:3: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   15 |   scanf("%d",&b[j]);
      |   ^~~~~~~~~~~~~~~~~

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